Topic: kvm switch hell: please advise :)

[devnullius]

(the hell part will follow once I've got a decent setup)

For now, I am looking for a new KVM switch (http://en.wikipedia.org/wiki/KVM_switch).

This is harder than it looks. Last week I've spent 40? 50? hours of investigating all kind of brands, reviews & comments, slowly getting to an end-list (still with questions open - SO MUCH to know!).

Short introduction... Things to look for / things I am looking for.

Budget? I started at €100, went to 200 and now I am up to €400 and even €600 (it is THAT important to me - all my computers & screens combined costed me less than 600 ;p).

Technology? USB (with optional PS/2 very appreciated). DVI or VGA. Audio support. Dual-head (or triple or quad) appreciated, but not obliged. At least support for 4 ports (clients/CPUs).

Problem? USB. And also: EDID / Windows 7.

Why problem? USB support is very complex with KVM Switch technology (the reason why PS2 switches still are sold at full price). Complex mouses and keyboards (wireless, G5, ...) will introduce all kinds of problems. Also, to remember video settings correctly (Windows 7 introduced hardware EDID based recognition & communication for screens), EDID must be supported. Details are unclear, but as far as I can tell (PLEASE correct me!) there are two main EDID support systems: ddcb2 & ddc. DDC is the best option (& newest). But ddcb2 should do the trick too - unclear about the differences...

Some questions I wrote down for myself... Copy Paste:
"Question: difference synchronious sound vs. regular sound (with mic + speaker)

Q's:
- does it support mixed digital & analog DVI usage?
- can I safely use regular DVI/VGA/HDMI adapter plugs? And also: mix them?
- does it have hotkey reset for keyboard & mouse? Is reset needed? Having to walk and unplug USB or powering off the switch is a big NO NO. My current D-Link PS/2 switch offers hotkey reset, which is brillant. For PS2 ;)
- in general: is full EDID support supported? :)  Or is it Emulated? Or is there no difference here?
Does it offer All-time full DDC/EDID emulation for video compatibility and stability? OR
do only connected and focussed CPUs receive full signal set?
- I want to have a constant connection, even when not focussed. So I KNOW there won't be any display or USB problems.
- how many years warranty? 1, 2, 3 or even more?"

In my very limited experiences, the biggest problem is USB support. Which is lacking on pretty much every (decent) switch out there... Display on my simple PS2 D-Link never was an issue, except for some BIOS / Pre-boot problems for some hardware once in a while...
Adder seems to have solved it, others try (very well to very badly: in general, I cannot find any devices WITHOUT bad reviews due to USB... Adder's devices are going under the radar, not many (if any) comments exist...).

In the reply next I'll post my end-list - a list I hope I can greatly alter with the help of SCF-community.

Karma!

Devvie


~~~ notemail@facebook.com ~~~
 
Cuisvis hominis est errare, nullius nisi insipientis in errore persevare
——
All spelling mistakes are my own and may only be distributed under the GNU General Public License! – (© 95-1 by Coredump; 2-013 by DevNullius)

[devnullius]

Here used to be my list of "chosen devices".

That list has evolved to this better place: http://scforum.info/index.php/topic,8018.msg20209.html#msg20209


I added a few devices curtsy by;
http://www.takeitnow.nl/categorie/netwerk/kvm_switches/p-1-100/)
http://unsorted.hardware.nl/search_products.php?keywords=uniclass%20switch
https://www.google.nl/#hl=en&safe=off&output=search&sclient=psy-ab&q=%2B%5B%22kvm+switch%22%5D+dual-mode+%2B(%5B%22displayport+1.2%22%5D+OR+%5B%22display+port+1.2%22%5D)&qscrl=1&oq=%2B%5B%22kvm+switch%22%5D+dual-mode+%2B(%5B%22displayport+1.2%22%5D+OR+%5B%22display+port+1.2%22%5D)&gs_l=hp.3...2133.2133.0.3188.1.1.0.0.0.0.266.266.2-1.1.0.les%3B..0.0...1c.2.4.psy-ab.rsHh_749gKE&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&bvm=bv.42768644,d.d2k&fp=e15db191cba4d770&biw=1130&bih=580

---

----> YOUR TIPS NEXT? YOUR DISSES??  Let me and US know xx



Karma,

devnullius

[Samker]

D., unfortunately, I'm not so familiar with this. 

[devnullius]

@Samker... Good! You can learn something new ;p

@Self... TRIM this list DOWN... That's an order!

Karma,

devnullius

[devnullius]

I posted a copy of my questions and findings @ http://www.tomshardware.co.uk/forum/67554-29-some-models-good-switches-2013

Next reply will be a new - more sorted - list. I'll trim it down, even if it's the last thing on Earth ;p

Also, I'll re-investigate DisplayPort devices. At first totally ignored by me, but it's the future and there seem to be a lot of converter plugs available... With Ttrue USB & EDID, that shouldn't be a problem... Shouldn't... :s

Karma!

devnullius

[devnullius]

New list, getting there...   

*** By brand...

--> ADDER (aka INTRONICS in Benelux)

(ADDERView 4 PRO DisplayPort) (AV4PRO-DP-EURO) aka (Intronics Ad2000 adderview 4 pro dp kvm switch (AD2000))
OFFICIAL PAGE: http://www.adder.com/products/adderview-4-pro-displayport
€560 @ http://www.takeitnow.nl/product/6631433/?c_id=972&channel_code=40&product_code=44733668&utm_source=tweakers.net
Single head (4x). True USB Emulation. Full DDC support. Always on feature. DisplayPort v1.1, not 1.2.
QUESTION: can I easily use DisplayPort converters? Is it dual-mode for backward compatibility?
QUESTION: is it suitable for 3D video? Bandwidth is more than sufficient? All extreme resolutions supported.


(AV4PRO-DVI-Dual-EURO)
OFFICIAL PAGE: http://www.adder.com/products/adderview-4-pro-dvi-multiscreen
I cannot find European resellers The few that seem to offer it, appear to have the wrong photos to begin with?
If DisplayPort is not suitable, and VGA to old-school, this device would be perfect (depending on price).
Dual head (4x). True USB Emulation. Full DDC support. Always on feature. AdderView Pro features full dual link DVI video delivering 4 megapixel resolutions at 60Hz. Because the AdderView features DVI-I, you can also use a mixture of digital and analogue sources without swapping cables. The extended DDC EDID profile ensures that the switched graphics card is always optimised to work with your screen. The dual link DVI capabilities enable users to work at very high resolutions including 2K (2048 x 1080) for film post production or WQXGA (2560 x 1600) for detailed medical imaging.


--> ATEN

(ATEN CS1784A) (USB DVI Dual Link KVMP Switch)
OFFICIAL PAGE: http://www.aten.com/products/productItem.php?pcid=2005010513171002&psid=20070130114411002&pid=2010120816561001&layerid=subClass3
Approx. €220; http://tweakers.net/pricewatch/282026/aten-cs1784a/specificaties/
Video is 3D ready and all that, very impressive. DynaSync (their way of "full" DDC). BUT: Complete keyboard emulation for error-free booting is promised... All in all, looks like an excellent choice and well within budget! Dual Link, meaning: mixed DVI (analog/digital) is possible. NOT dual head or dual screen... Dual LINK ;p

(ATEN CS1644) (USB 2.0 DVI Dual View KVMP Switch)
OFFICIAL PAGE: http://www.aten.com/products/productItem.php?model_no=CS1644
(press "Informatie") http://www.centralpoint.nl/toetsenbord-video-muis-kvm-switches/aten/cs1644-art-cs1644-num-317888/
Approx. €365; http://www.hardwarewebwinkel.nl/netwerk-splittersextenders-switches-aten-cs1644-port-dual-view-kvmp-switch-p-953656.html?utm_campaign=pricecompare&utm_content=textlink&utm_medium=cpc&utm_source=tweakers
DVI 4 port Dual View. 3D Video etc. DynaSync for EDID storage. Complete keyboard emulation for error-free booting (but again, nothing on HOW USB is emulated… Or if it is DDC2B or DDC... :s)


--> BLACKBOX.nl

(BlackBox KV2004A single head €460) (BlackBox KV2204A dual head €913)
OFFICIAL PAGE: http://www.blackbox.nl/nl-nl/si/12446/ServSwitch-Wizard-DVI-DL-USB-Multivideo/S1.O3/kv2004a
More information: Emulated USB ++ Transparant USB ++ "Ghost"-features (update table with DDC/EDID of troublesome screen).


--> IOGEAR

(Iogear GCS1784) (4-Port DVI KVMP Switch with 7.1 Audio & Cables)
OFFICIAL SITE: http://www.iogear.com/product/GCS1784/
€410; http://www.salland.eu/product/233998/iogear-4port-dual-dvi-kvmp-switch-gcs1784.html?ref=2
DDC? Custom Display Emulation Technology solution. Not a constant-on connection? USB? "Complete keyboard and mouse emulation for error free booting and real-time switching". Does not sound like the new generation of true USB transparancy... I should ask support.
DVI 4x. DVI digital + analog (dual link). No dual-display.

(IOGEAR GCS1794) (4-Port HDMI Multimedia KVMP Switch)
OFFICIAL SITE: http://www.iogear.com/product/GCS1794/
€300; http://azerty.nl/producten/product_detail/1610/541774/iogear-gcs1794-video-audio-schakelaar-4-x-hdmi-desktop.html
Same questions as for IOGEAR GCS1784. Also another question: can I safely use HDMI to DVI converters...? I should ask support. But again: USB support seems not up to par :s


--> D-LINK

(D-Link 4-Port USB KVM Switch) (DKVM-4U)
OFFICIAL SITE: http://www.dlink.com/us/en/home-solutions/connect/kvm-switches/dkvm-4u-4-port-usb-kvm-switch ($60)
Although very basic, no sound, I added this 4x VGA USB switch to the list because I currently own a D-Link, PS/2. I never thought it gave me any problems (just wait for my hell article) but all in all… It does not support USB and still I used USB to PS/2 converters and even 6m long USB extension cables attached to them… Which probably causes all my hell experiences for the last 2 years… Still, all in all I always liked the switch (not knowing anything about the USB hell caused by it!). Video always switched on and is remembered, it seems to have no limitations on video resolution, and BIOS often is available and usable. Windows 7 or 8 never seemed to have display problems. Best feature is the "reset" hotkey. Home Home p for KB + Mouse reset; Home Home m for just a mouse reset (but I do not know if the same goes for this model…) Also, Hot-swappable! And yes, it too came cheap (€50 3 years ago?). So I might even just buy this device, see if it works for me and let me forget about all the complex models. Then again… I am kinda greedy at the moment :>

(D-Link 8 Port PS2 / USB Combo KVM Switch KVM-440) (KVM-440)
http://www.excaliberpc.com/609559/d-link-kvm-440-port-ps2-usb.html#TabDescription (€250).
Should be removed from my list: Console (& hotkeys) only with PS/2 keyboard / mouse. But still, I cannot remove it yet… Windows 7 supported (DDC & DDC2). Hot-swappable. But no complex mouses or keyboards. Comes with special cable that looks like this one: http://takas.lk/computer-electronics/kvm/d-link-kvm-401-4-in-1-ps2-usb-kvm-cable-for-kvm-440.html - it has USB & PS/2 + VGA in one cable. No sound.


--> UNICLASS

(UNICLASS Switch AL-204A 4-Port DVI / USB2. 0-TT) (AL-204A)
OFFICIAL SITE: http://www.uniclass.com.tw/english/01_product/02_detail.php?pid=1242
€365; http://unsorted.hardware.nl/AL-204A
With TTU (True Transparant USB, like Adder's!), full advanced DDC with Active Sync Replication.
4x DVI dual-link single-head.
TTU explanation: http://www.uniclass.com.tw/english/01_product/01_list.php?mid=79&id=155
Note to self: check if they have DisplayPort models with DisplayPort++ & v1.2 support ;p

(UNICLASS Desktop HDMI or DisplayPort KVM Switches) (AI834A / AP834A / AP-204A)
List of devices: http://www.uniclass.com.tw/english/01_product/01_list.php?mid=79&id=156
-> AI-834A: (http://www.uniclass.com.tw/english/01_product/02_detail.php?pid=1250) (4-Port Smart Touch HDMI USB KVM Switch w/ USB 3.0 Hubs)
QUESTION FOR SUPPORT: QUESTION: can I safely use passive converters with this model?
-> AP-204A: (http://www.uniclass.com.tw/english/01_product/02_detail.php?pid=239). 4x DisplayPort, v1.1. TTU (the product page does not mention TTU but support confirmed it is TTU). SINGLE LINK! I know I want DisplayPort++ aka dual link DP, but I must admit: I do not know what single link would actually mean to me… I'll ask support ;p
-> AP-834A: 4x DisplayPort 1.1. TTU. SINGLE LINK!  I know I want DisplayPort++ aka dual link DP, but I must admit: I do not know what single link would actually mean to me… I'll ask support... 2 port USB 3 hub!! So bandwidth wise one could add about 20 USB 2.0 devices through extra 2.0 hubs… ;p


--> BELKIN

(Belkin OmniView Secure 4-Port KVM Switch) (KVM switch - USB - 4 x KVM port(s) - 1 local user)
http://www.belkin.com/nl/IWCatProductPage.process?Product_Id=373469#
Military grade security sounds really cool. But what about EDID & USB?? I requested support with informatique.nl.
€355; http://www.takeitnow.nl/product/196953
Big Brother dual head model: http://www.takeitnow.nl/product/6657921



*** NEWLY ADDED from the original list & Reason(s) for adding...

--> StarTech SV431DPUA 4 Port USB DisplayPort KVM Switch with Audio 7.1
OFFICIAL PAGE: http://ca.startech.com/Server-Management/KVM-Switches/4-Port-USB-DisplayPort-KVM-Switch-with-Audio~SV431DPUA
Added because: Fully compatible with Mini-DisplayPort, HDMI, and DVI adapters.
BUT: DDC2B, not DDC. No Multi Head / Display. Supports hot-plug, un-plug and link status-failure detection. No information about true transparant usb.
BUT reviews are not always raving... One review WITH MORE TECHNICAL BACKGROUND INFO (about display emulation, which makes the computer think that the monitor is still there when you have switched to another port on the KVM): http://www.amazon.com/gp/cdp/member-reviews/A37GGTWAYXFU4P/ref=cm_pdp_rev_title_1?ie=UTF8&sort_by=MostRecentReview#R2DVAQE0YRIWG3

--> IOGEAR GCS1644 4-Port Dual View Dual-Link DVI KVMP Switch w/ Audio
(from: http://www.kvm-switches-online.com/gcs1644.html)

--> (from http://www.testfreaks.com/kvm-switches/). <IN EDIT>
--> (from http://www.kvmgalore.com/shopping/group.php?group_id=12). <IN EDIT>



*** REMOVED from the original list & Reason(s) for removing...

--> ADDER CCS4USB Command and Control switch
http://www.kvm-switches-online.com/av4pro-dvi-us.html
Removed because: every CPU needs its own screen. This is not an option for me. Great solution, reasonably prised (<€450). True USB simulation.

--> ATEN CS1734B
OFFICIAL PAGE: http://www.aten.com/products/productItem.php?model_no=CS1734B
Approx. €130; http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=6047996&CatId=598
4 port DVI. PS/2 or USB. Superior video quality; 2048 x 1536; DDC2B only. Console mouse port emulation / bypass feature supports full mouse driver and multifunction mice (....)
EDIT: NO INFORMATION 'bout USB support. Is it 'fancy' or old-school buggy usb emulation? It appears the latter... I shall ask their support one of these days...

--> ATEN CS1744
http://www.aten.com/products/productItem.php?model_no=CS1744
See CS1644, but with VGA. Comes with PS/2 to USB cable.

--> Aten CS1944 (4-Port USB 2 MiniDP Dual View)
OFFICIAL PAGE: http://www.aten.com/products/productItem.php?model_no=cs1944
http://www.kvm-shop.nl/nl/KVM-Producten/Desktop-KVM-Switches/CS1944-4-Port-USB-2-MiniDP-Dual-View, approx. €610.
No information about EDID or USB. Video itself has it all, even 3D etc. I'll call support (kvm-shop.nl) next week. I'll also ask if (mini-)displayport is easily / safely convert-able with appropriate plugs... But most interested am I in USB support / emulation. Also, I do not understand how dual view works in this specific device... :s
Dual Mini DisplayPort (4x). 3D video. Connected only when focused, not an always-on system? So more bugs? Mini DisplayPort 1.1a & HDCP compatible - does this mean it is fully DDC compliant? No mention of DynaSync. Better look at CS1784A - site promisses more, so I guess the CS1944 is older model...? For now: removed from list

--> Aten CS74U 4-Port USB KVM Switch
http://www.aten.com/download/download_m.php?modelNo=CS74U
Very "cheap" (€85). Nothing about EDID or USB. I'll call support (kvm-shop.nl) next week.

--> Aten CS1762A 2-Port DVI USB KVM Switch
http://www.testfreaks.com/kvm-switches/aten-cs1762a/reviews/
€130.

--> IOGEAR GCS1924
http://www.iogear.com/product/GCS1924/ ($880)
3 Years warranty & Mini DisplayPort 1.1a & HDCP compatible (dual head). No information about Dual Mode (DVI etc. compatibility). Mainly removed due to price... Mixed reviews: http://alatest.nl/reviews/hubs-switches/iogear-gub431-print-server/po3-103935941,42/

--> IOGEAR GCS1204G 4-Port Dual-Link DVI KVMP Pro
http://www.iogear.com/product/GCS1204G/
€290;  http://www.takeitnow.nl/product/6395041, popular seller.
Same as other models, same questions. Dual-link, not dual-head. 4x DVI.
If budget of €400 is not too pricey, look at the GCS1794... Better sound.

--> IOGEAR GCS1642 KVM switch
OFFICIAL PAGE: http://www.iogear.com/product/GCS1642/
http://www.centralpoint.nl/toetsenbord-video-muis-kvm-switches/iogear/gcs1642-art-gcs1642-num-477009/
2x DVI dual link + dual head. Further: same questions as with other IOGEAR product...

--> IOGEAR GCS1104 4-Port DVI KVMP Switch with Audio and Cables
OFFICIAL SITE: http://www.iogear.com/product/GCS1104/
€225; http://www.salland.eu/product/755553/iogear-4-port-dvi-kvmp-switch-gcs1104.html?ref=2
Extra link: http://www.testfreaks.com/kvm-switches/iogear-gcs1104/
4x DVI (digital only?). DDC2B (with DynaSync). Same USB questions, it does not look like IOGEAR uses true transparant USB...

--> IOGEAR 16-Port USB PS/2 Combo KVM Switch with Cables GCS1716KITU
http://www.takeitnow.nl/product/5969961#Technische%20details (€590)
DDCB2; nothing about USB support. USB 1.1 only! Shouldn't be in this list, but for googlers... xx

--> StarTech SV431DDVDUA 4 port 1xDVI+1xVGA USB KVM switch with Audio and USB 2.0-hub
OFFICIAL SITE: http://eu.startech.com/Server-Management/KVM-Switches/4-Port-DVI-VGA-Dual-Monitor-USB-KVM-Switch-with-Audio-USB-20-Hub~SV431DDVDUA
€260; (Dutch site) http://azerty.nl/producten/product_detail/1610/284516/startech-com-starview-4-port-dvi-vga-dual-monitor-kvm-switch-usb-with-audio-amp-usb-2-0-hub-kvm-audio-usb-switch-usb-.html
4x (1x VGA + 1x DVI) multi monitor. Semi dual link: so either all CPUs are DVI digital OR DVI analog. No mixing! No information about USB simulation. No information about EDID. I should ask support, but I bet I'll be going to find a lot of complaining users due to USB problems…? We'll see, later ; )

--> StarTech SV431DD2DUA 4 PORT DUAL DVI USB KVM SWITCH met AUDIO
OFFICIAL SITE: http://eu.startech.com/Server-Management/KVM-Switches/4-Port-Dual-DVI-USB-KVM-Switch-with-Audio-20-Hub~SV431DD2DUA
€325;  http://www.takeitnow.nl/product/4250381 or http://www.newegg.com/Product/Product.aspx?Item=N82E16817707204
4x (2x DVI) multi monitor. Semi dual link: so either all CPUs are DVI digital OR DVI analog. No mixing! No information about USB simulation. No information about EDID. Probably not always-on, only focussed CPU.

--> BlackBox ServSwitch DT DVI USB
OFFICIAL SITE: http://www.blackbox.nl/nl-nl/si/12321/ServSwitch-DT-DVI-USB/V1.S1.F5165.O3/kvm+switch (€205)
MANUAL: http://www.blackbox.nl/nl-nl/Download/ItemFile.cfm?IdItemFile=10215&IdLanguage=2&nocache=false
4x DVI. Emulated DDS. KV9614A comes with USB HID emulated instead of USB HID only. Device looks very professional! But is it up to par with true transparent USB? And how good is the emulated DDS? Only Vista is supported, not 7, according to the manual… When it fails, is there a reset function or should I unplug / whatever? I will contact them, for now: off the list!

--> BlackBox ServSwitch DT DVI USB MultiVideo
OFFICIAL SITE: http://www.blackbox.nl/nl-nl/fi/1431/12432/ServSwitch-DT-DVI-USB-MultiVideo/ (€285)
MANUAL: http://www.blackbox.nl/nl-nl/Download/ItemFile.cfm?IdItemFile=9167&IdLanguage=2&nocache=false
4x Dual Head Dual Link DVI. VGA with adapter(s). DT DVI MultiVideo supports one emulated USB channel. Same remarks as the DVI USB above! Of the 3 BlackBox system I found, this one looks the best and most versatile - besides no DDC2B it only (?) has USB HID emulation…

--> BlackBox ServSwitch DT DVI with Bidirectional Audio
OFFICIAL SITE: http://www.blackbox.nl/nl-nl/fi/1431/12798/ServSwitch-DT-DVI-with-Bidirectional-Audio/ (€245)
Supports DDC2B emulation. Specifications do mention Windows 7 for this device, also it does mention DDC2B. No information about USB HID emulation.
Off the list… Compatible with DVI flat screens (digital only). So, no ;p Nice looking device though!

--> LINKSKEY 4-port Dual Monitor DVI/DVI USB Audio & Mic KVM Switch w/ Cables (LDV-DM204AUSK)
OFFICIAL SITE: http://www.linkskey.com/detail.php?Productid=1043
$320; http://www.newegg.com/Product/Product.aspx?Item=N82E16817402040
Seems to have it all, this device. True transparent USB, DDC, 4x DVI single link dual head. BUT… All user comments I read about this device are: it will break down! The hardware seems to be really really bad and unless I can get it with a full 5 year warranty (1 is offered), I'd pass this one. With pain in my heart

--> UNICLASS (NO RESELLERS (Netherlands) anywhere
      -> http://www.uniclass.com.tw/english/01_product/02_detail.php?pid=29 (AL-504V Dual-Link Dual Monitors DVI/VGA KVM Switch)
      -> http://www.uniclass.com.tw/english/01_product/02_detail.php?pid=141 (AL-504D Dual-Link Dual Monitors DVI KVM Switch)
      -> http://www.uniclass.com.tw/english/01_product/02_detail.php?pid=144 (AIEP04A HDMI USB KVM Switch)

--> Intronics Ab7970 4 poorts dvi/usb switch+audio (AB7970)
OFFICIAL SITE: http://intronics.nl/netherlands/nl_NL/product/dvi-kvm-switch-ab7970
SITE SUCKS. Not much information, and you need to be a reseller for more... Well, never mind than!
€324 - €400; http://www.takeitnow.nl/product/4701591

--> ROSE MDM-4T2DDL/A1 1X4 KVM Switch, DVI-I, Dual-Link, Dual-Video, USB 2.0
OFFICIAL PAGE: http://www.rose.com/htm/multivideodvi.htm
Industrial equipment (good), but no (European) resellers... Not even price indications! Too bad, still added to "The List" ;p
Single monitor model: http://www.kvm-switches-online.com/kvm-4tddl-a1.html (KVM-4TDDL/A1)

--> ROSE Orion LC DVI / USB 2.0 KVM Switch Crosspoint Router Multiplex Repeater
OFFICIAL PAGE: http://www.rose.com/htm/orionlc.htm
VERY flexible device! Probably way above budget Just putting it here for completeness. Nothing about USB or DDC...

--> HighSecLab K524E 4-Port Dual-head DisplayPort 3rd-Generation Secure KVM Switch
(CPN06446 [Europe] // CPN06447 [UK] // CPN06448 [US, Canada])
OFFICIAL PAGE: http://www.highseclabs.com/K524E_Secure_DP_KVM_Switch.html
Reason for adding? Latest DisplayPort 1.2 version! No price indication available
Also: The K524E Secure KVM is a Dual-head version that supports two user displays. Each computer is coupled to the KVM through two DisplayPort cables. NO INFORMATION ABOUT dual mode for backward DVI/HDMI/VGA compatibility... RDC (Remote Desktop Controller) port enables simple interface with HSL's RDC440 controller.
I think it has an USB hub, but I am not clear (yet)
REASON FOR REMOVING: so SAD, but as of yet there are no DP 1.2 converters available (PLEASE CORRECT ME IF I AM WRONG!). READ MORE here: http://scforum.info/index.php/topic,8018.msg20221.html#msg20221

--> HighSecLab K244/E Dual-head 4 Ports DisplayPort 3rd-Generation Secure KVM Switch
OFFICIAL PAGE: http://www.highseclabs.com/K244_Secure_KVM_Switch.html
Only USB Mouse & Keyboard, no other USB devices?
REASON FOR REMOVING: so SAD, but as of yet there are no DP 1.2 converters available (PLEASE CORRECT ME IF I AM WRONG!). READ MORE here: http://scforum.info/index.php/topic,8018.msg20221.html#msg20221

--> ADDERView 4 PRO VGA MultiScreen - (AV4PRO-VGA-Dual) (Intronics Ad3054)
OFFICIAL PAGE: http://www.adder.com/products/adderview-4-pro-vga-multiscreen
€522 @ http://www.salland.eu/product/980033/adder-adderview-pro-multi-screen-kvm-audio-usb-switch-usb-4-x-kvm-audio-usb-1-lokale-gebruiker-desktop-av4pro-vga-dual-euro.html?ref=2
Dual head (4x). True USB Emulation. Full DCC support. Always on feature.
QUESTION: can I easily use VGA to DVI/HDMI converters? VGA <-> DVI should not be a problem.
QUESTION: is it suitable for 3D video? What is the bandwith per channel? Which maximum resolutions are supported?
MORE BACKGROUND INFO about max. supported VGA resolutions: http://superuser.com/questions/205453/maximum-resolution-through-vga-dvi-hdmi-etc
REASON FOR REMOVING: I'm first looking at the DP/DVI models...

--> ADDERView PRO 4-Port USB DVI KVM Switch (AV4PRO-DVI-EURO) aka (Intronics Ad3008)
OFFICIAL PAGE: http://www.adder.com/products/adderview-4-pro-dvi
€425 @ (probably correct device) http://www.takeitnow.nl/product/4153451/ .
AdderView Pro features full dual link DVI video delivering 4 megapixel resolutions at 60Hz. Because the AdderView features DVI-I, you can also use a mixture of digital and analogue sources without swapping cables. The extended DDC EDID profile ensures that the switched graphics card is always optimised to work with your screen. The dual link DVI capabilities enable users to work at very high resolutions including 2K (2048 x 1080) for film post production or WQXGA (2560 x 1600) for detailed medical imaging.
REASON FOR REMOVING: I'm first looking at the DVI models...




    -=-
devnullius

[devnullius]

http://en.wikipedia.org/wiki/Display_Data_Channel

(snippet)

DDC1
DDC1 is a simple, low-speed, unidirectional serial link protocol. Pin 12, ID1 functions as a data line that continuously transmits the 128-byte EDID block, and the data clock is synchronised with vertical sync, providing typical clock rates of 60 to 100 Hz.
Very few display devices implemented this protocol.
[edit]DDC2
The most common version, called DDC2B, is based on I²C, a serial bus. Pin 12, ID1 of the VGA connector is now used as the data pin from the I²C bus, and the formerly-unused pin 15 became the I²C clock; pin 9, previously used as a mechanical key, supplied +5V DC power up to 50mA to drive the EEPROM, this allows the host to read the EDID even if the monitor is powered off. Though I²C is fully bidirectional and supports multiple bus-masters, DDC2B is unidirectional and allows only one bus master - the graphics adapter. The monitor acts as a slave device at the 7-bit I²C address 50h, and provides 128-256 bytes of read-only EDID. Because this access is always a read, the first I²C octet will always be A1h.
DDC2Ab is an implementation of the I²C-based 100 kbit/s ACCESS.bus interface, which allowed monitor manufacturers to support external ACCESS.bus peripherals such as a mouse or keyboard with little to no additional effort; such devices and monitors were briefly available in the mid 1990s, but disappeared with the introduction of USB.
DDC2B+ and DDC2Bi are scaled-down versions of DDC2Ab which only support monitor and graphics card devices but still allow bidirectional communication between them.
DDC2 is not exclusive to the VGA connector, as both DVI and HDMI connectors feature dedicated DDC2B wires.

Karma, please, for my head tumbles by now :s

;) devnullius

[devnullius]

FURTHER BACKGROUND, INFORMATIONAL LINK:
http://forums.anandtech.com/showthread.php?t=2248863

FROM: http://en.wikipedia.org/wiki/DisplayPort

(snippets)

"The DisplayPort signal is not compatible with DVI or HDMI. However, dual-mode DisplayPorts are designed to transmit a single-link DVI or HDMI protocol across the interface through the use of an external passive adapter that selects the desired signal and converts the electrical signalling from LVDS to TMDS. VGA and dual-link DVI, on the other hand, require active adapters to convert the protocol and signal to the desired output and do not require dual-mode DisplayPorts. VGA adapters are powered by the DisplayPort connector, while dual-link DVI adapters may rely on an external power source (see compatibility with HDMI, DVI and VGA). (http://news.hopeindustrial.com/2011/transition-to-displayport-connectors/)"

and

"Dual-mode DisplayPort (also known as DisplayPort++[26]) can directly output single-link HDMI and DVI signals using a simple passive adapter that adjusts from the different connector and the lower voltages used by DisplayPort. [http://www.displayport.org/faq/faq-archive/] + [http://www.displayport.org/] When dual-mode chipset detects that a DVI or HDMI passive adapter is attached, it switches to DVI/HDMI mode which uses the 4-lane main DisplayPort link and the AUX channel link to transmit 3 TMDS signals, a clock signal and Display Data Channel data/clock. Dual-mode ports are marked with the DP++ logo; most current DisplayPort graphics cards and monitors offer this mode."

Does look an important feature for ANY DigitalPort KVM Switch ; )

"In January 2013, a new VESA specification was released called DisplayPort Dual-Mode Standard version 1.1, which brings dual-mode capabilities on par with HDMI 1.4, allowing a TDMS clock rate of up to 300MHz, 1080p deep color, 4K resolution, and stereoscopic 3D formats. Passive adapters and ports which support the new data rate will be marked 'Type 2', and will be backwards compatible with existing 'Type 1' ports. [http://www.vesa.org/featured-articles/vesa-introduces-updated-dual-mode-standard-for-higher-resolution-interoperability-with-hdmi-displays/]"

Also:

"A notable limitation of Type 1 dual-mode is that it can only transmit single-link DVI (and HDMI), as the number of pins in the DisplayPort connector is insufficient for dual-link connections. Also, it is limited to a TMDS clock rate of 165 MHz. As a result, an active converter is needed for Dual-Link DVI, HDMI 1.3+, and analog component video such as VGA. Some of these active adapters can rely on the +3.3 V wire in the DisplayPort connector for the conversion, but other types of active conversion, such as Dual-Link DVI, require external power that is often pulled from an available USB port.[http://web.archive.org/web/20110814062309/http://www.bizlinktech.com/future_displayport.html]"

"VESA anticipates that HDMI and DVI conversion will eventually be handled by active adapters which act as DisplayPort Sink devices, in order to facilitate easier updates to latest HDMI and DisplayPort specs, and work with dual-link HDMI, DisplayPort connections with either fewer than 4 lanes or different data rates, and multiple DisplayPort streams. It should be noted that DVI 1.0 spec was finalized in 1999 and the DVI industry consortium has since disbanded, so future updates to DVI specification are unlikely; also, although dual-link HDMI Type B connector is defined in the HDMI specification, it has not seen any practical use as of 2012."

And lastly the versions...

"Versions

[]1.0 to 1.1
DisplayPort 1.0 allows a maximum of 8.64 Gbit/s data rate over a 2 meter cable.[12] DisplayPort 1.1 also allows devices to implement alternative link layers such as fiber optic, allowing a much longer reach between source and display without signal degradation,[13] although alternative implementations are not standardized. It also includes HDCP in addition to DisplayPort Content Protection (DPCP).
[]1.2
DisplayPort version 1.2 was approved on December 22, 2009. The most significant improvement of the new version is the doubling of the effective bandwidth to 17.28 Gbit/s, which allows increased resolutions, higher refresh rates, and greater color depth. Other improvements include multiple independent video streams (daisy-chain connection with multiple monitors), facilities for stereoscopic 3D, increased AUX channel bandwidth (from 1 Mbit/s to 720 Mbit/s), more color spaces including xvYCC, scRGB and Adobe RGB 1998, and Global Time Code (GTC) for sub 1 µs audio/video synchronisation. Also Apple Inc.'s Mini DisplayPort connector, which is much smaller and designed for laptop computers and other small devices, is compatible with the new standard"

So... I think I'll restart searching for KVM switches with this in mind... And so we learn... Again... Do research first ; ) BUT I do not think I'll find many displayport KVM switches out there, let alone Dual-Mode...?



No Amen yet, but Karma still!

devnullius

[devnullius]

SOURCE: http://superuser.com/questions/118957/converting-displayport-and-or-hdmi-to-dvi-d

EXTRA INFORMATIONAL LINKS:
HDMI adapter for regular DVI: http://dx.com/p/gold-plated-hdmi-male-to-dvi-24-1-female-adapter-32388
DisplayPort adapter for regular DVI: http://dx.com/s/displayport+male+to+dvi+female+adapter
1:2 DisplayPort version 1.2 Dual-mode Source Demultiplexer with DisplayPort and TMDS Outputs: http://www.hy-line.de/firmengruppe/hy-line-computer-components/hersteller/parade/ps8336/


Background: this article talks about 1 specific video-card. Still, I thought to post some thoughts and problems they ran into - it seems this card is not dual-mode (which could make sense: it has 2x DVI + 1x HDMI + 1x DP...).

Snippets...

"is it possible to convert either the HDMI or DisplayPort to DVI? If so, how? And which one is easier/cheaper to convert?

I did a little research and it looks like there isn't a simple "dongle" method. I found this DisplayPort to DVI-D Dual Link Adapter  but it's $120; almost cheaper to buy a new monitor that supports HDMI or DisplayPort inputs at that point!

There's also a HDMI to DVI-D adapter at Monoprice  but I'm not sure it will work, either.

AnandTech seems to imply  that you do need the DisplayPort-to-DVI:

The only catch to this specific port layout is that the card still only has enough TMDS transmitters for two ports. So you can use 2x DVI or 1x DVI + HDMI, but not 2x DVI + HDMI. For 3 DVI-derived ports, you will need an active DisplayPort-to-DVI adapter."

"From what I heard, the cheap adapters don't work because you need something that generates an TDMS Signal. The cheap adapters expect the source to already support a TDMS Signal and more or less just convert mechanically.

I have a post here . I ended up buying a $100 Dell Adapter which works, but fails whenever power savings comes into play (I basically have to unplug/replug to "reset" the adapter).

In hindsight, I would have bought a Display Port Monitor or a second card, both options would have been cheaper and less problematic than the Adapter, but I already had 3 screens.

Edit: After 2 Weeks, I really regret it. The adapter just "crashes" after some time (black screen, sometimes it turns on, off, on, off... My Monitor always stays on, so it's the adapter not generating a picture signal anymore). I'll try a USB-Charger next as they hopefully have more power, but I now really regret not getting a DP Monitor instead.

Video of DisplayPort-DVI Adapter Suckage: http://vimeo.com/10425439 "

Karma,

devnullius

[devnullius]

(English translation will follow...)

Copy-Paste:
"Er zijn voor KVM-switches zoals onze ServSwitch familie, twee typen KB/MS ondersteuning:
- emulated
- transparant
 
Emulated wil zeggen dat u niets anders dan standaard muizen en toetsenborden (‘USB-HID’) kunt aansluiten omdat dat de communicatie is die de switch ‘kent’. Dit stelt de switch in staat om de datastroom van keyboard en muis te analyseren en hot-keys te herkennen. En de switch kan hiermee de PC’s laten denken dat keyboard en mouse constant aangesloten zijn waardoor wachttijden bij het schakelen niet voorkomen.
 
Transparant wil zeggen dat de switch alle USB-apparatuur aan de PC’s kan koppelen, maar hot-key herkenning is onmogelijk en bij het schakelen vergt het enige tijd voordat het OS de muis en toestenbord weer herkend heeft. U kunt dit vergelijken met het fysiek omsteken van muis en toetsenbord.
 
Beide methodes hebben hun voor- en nadelen.
 
Deze switch (KV9614A) heeft dus geen Transparant USB ondersteuning, u kunt er vier USB-HID compatible devices op aansluiten en met Hot-Keys schakelen tussen de PC’s. Zoekt u DVI-D en Transparant USB dan moet u voor de KV9604A kiezen.
 
Emultated DDC werkt in veel gevallen goed. Maar is gebaseerd op een interne tabel en het komt voor dat deze niet toereikend is in bepaalde situaties. Er is geen optie bij deze switches om de DDC-tabel te updaten. In dat geval raden wij een DVI-D DDC Ghost (ACS2100A) aan.
http://www.blackbox.nl/nl-nl/fi/1449/12272/DVI-D-DDC-Ghost-Emulator/?ac=acs20
 
Een andere benadering is de KV2004A:
http://www.blackbox.nl/nl-nl/si/12446/ServSwitch-Wizard-DVI-DL-USB-Multivideo/S1.O3/kv2004a
Deze ondersteunt zowel Emulated USB als Transparant USB en kan de DDC/EDID-data van het gekoppelde scherm opslaan.

Hans de Waard, BlackBox.nl"

Karma...


devnullius