Hardware: - 1x Sapphire Ultimate R7 250 (1002:683f, 1x DVI, 1x HDMI, 1x DisplayPort, passive) - 2x Dell 3007-WFP HC (30", 2560x1600 @ 60) Software: - Ubuntu 14.04 - Kernel 3.13.0-27-generic - linux-firmware package version 1.127.2 Symptom: - DVI connection works just fine. - HDMI or DisplayPort just produces a garbled display, although the monitors are correctly detected by the driver in any case. I've then tried to use the later versions provided by the xorg-edgers Ubuntu PPA with the exact same result. Also, there are no errors or warnings in the Xorg logs that would point to a problem. I probably should note that the monitors only have dual-head DVI connectors, so for connecting DisplayPort, I used a DisplayPort-to-DVI cable and for HDMI, I used an HDMI cable plus an HDMI-to-DVI adapter. As the result is exactly the same in both cases, I expect that the cabling is fine. Also when connecting the second monitor to DVI instead of the first one its also fine, so it's not a monitor issue either.
I should also note that on a previous card (Radeon HD 4770) everything worked fine using two DVI connectors.
Created attachment 99700 [details] Xorg.0.log with second monitor on HDMI
Created attachment 99701 [details] Xorg.0.log with second monitor on DisplayPort
Created attachment 99702 [details] lspci -vnvn -s 01:00.0
Created attachment 99703 [details] Photo of corruption
You GPU (R7 250) only supports two digital links. You monitors require 2 digital links per monitor (4 total) when used in DVI mode. If you attach one via DVI, it uses both available links so there are no others available for HDMI or DP. You can use DP, but you need to use a direct DP connection or an active DP to DVI convertor since native DP will only require 1 link. Passive DP convertors will not work because your displays require 2 links.
Ouch! Thanx a lot for that info. Can you give me a hint where I can find such information in order to search for a card that works for me? Looking at the specs on the offical AMD site it doesn't tell me anything regarding this.
You can look up the asic family from the marketing name here: http://en.wikipedia.org/wiki/Ati_gpu R7 250 is Oland based. And these pages have some details of the hardware features on the asics: http://www.x.org/wiki/RadeonFeature/ http://www.amd.com/en-us/products/graphics/desktop/r7# http://www.amd.com/en-us/products/graphics/desktop/oem/r7# Dual-link DVI monitors require 2 links per monitor. Oland chips only support 2 digital links. Most other chips support 6.
Thanx a lot. So Cape Verde doesn't make any difference on the matter compared to Oland, obviously. I'll then go and find a proper card for me. Thanx again and sorry to have you bothered with such things... :)
(In reply to comment #9) > Thanx a lot. So Cape Verde doesn't make any difference on the matter > compared to Oland, obviously. Cape verde supports 6 digital links.
OK, then it is just the board that I have: http://www.sapphiretech.com/presentation/product/?cid=1&gid=3&sgid=1226&pid=2130&psn=&lid=1&leg=0 ...and that's the difference between the Verde Pro and Verde XTL, as I read from their specs: http://www.sapphiretech.com/archive/matrix-vga-1_4_057.xls
(In reply to comment #11) > OK, then it is just the board that I have: > > http://www.sapphiretech.com/presentation/product/ > ?cid=1&gid=3&sgid=1226&pid=2130&psn=&lid=1&leg=0 > > ...and that's the difference between the Verde Pro and Verde XTL, as I read > from their specs: > > http://www.sapphiretech.com/archive/matrix-vga-1_4_057.xls I'm not quite sure what you are asking. In addition to the number of links on the chip itself, you are limited by how the board is wired up. E.g., if your board only has one DVI port on it, you are limited to 1 dual-link DVI display since HDMI does not support duallink and DP requires an active adapter to support duallink DVI.
OK, so should I be trying with an active DP adapter first? I guess you mean such as this one: http://accessories.euro.dell.com/sna/productdetail.aspx?c=uk&l=en&cs=ukdhs1&sku=490-11917 ...then I could just go and buy myself a proper new card and don't mess with the cabling.
(In reply to comment #13) > OK, so should I be trying with an active DP adapter first? > > I guess you mean such as this one: > > http://accessories.euro.dell.com/sna/productdetail. > aspx?c=uk&l=en&cs=ukdhs1&sku=490-11917 > > ...then I could just go and buy myself a proper new card and don't mess with > the cabling. If your monitor supports DP natively, just use that. If it only supports dual-link DVI, you'll either need a card with two dual-link DVI connectors, or you'll need a card with 1 dual-link DVI connector and 1 DP connector with an active DP to dual-link DVI convertor.
Exactly. Well after some searching I think I'll just try with an active DP adapter because I really like the fact that the card is passive - I couldn't find any passive R7 card that has 2 dual-link DVI connectors - only cards with coolers and that's not really an option for the little box in question. Anyway, thanx a lot for your time. :)
Just to report back: Got it to work with an active DisplayPort to dual-link-DVI adapter (a StarTech DP2DVID2). However, EDID is lost and probed modes are completely wrong (fallback defaults?): EDID for output DisplayPort-0 Printing probed modes for output DisplayPort-0 Modeline "1024x768"x60.0 65.00 1024 1048 1184 1344 768 771 777 806 -hsync -vsync (48.4 kHz e) Modeline "800x600"x60.3 40.00 800 840 968 1056 600 601 605 628 +hsync +vsync (37.9 kHz e) Modeline "800x600"x56.2 36.00 800 824 896 1024 600 601 603 625 +hsync +vsync (35.2 kHz e) Modeline "848x480"x60.0 33.75 848 864 976 1088 480 486 494 517 +hsync +vsync (31.0 kHz e) Modeline "640x480"x59.9 25.18 640 656 752 800 480 489 492 525 -hsync -vsync (31.5 kHz e) To solve this I took the mode lines from the DVI connected monitor and manually specified it in the xorg.conf: EDID for output DisplayPort-0 Not using mode "1024x768" (hsync out of range) Not using mode "800x600" (hsync out of range) Not using mode "800x600" (vrefresh out of range) Not using mode "848x480" (hsync out of range) Not using mode "640x480" (hsync out of range) Printing probed modes for output DisplayPort-0 Modeline "2560x1600@60"x59.9 268.00 2560 2608 2640 2720 1600 1603 1609 1646 +hsync +vsync (98.5 kHz UP) Modeline "1280x800@60"x59.9 71.00 1280 1328 1360 1440 800 803 809 823 +hsync -vsync (49.3 kHz)
Created attachment 101038 [details] xorg.conf with manual configuration for DisplayPort
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