ATI card guru? dual-card-dual-head? breaks 3d [Solved]

[anomaly65]

Hi all,

Have been running dual displays for nearly 20 years now. Hard to give up that habbit

Purchasedd a pair of excellent crossover branded IPS displays (2560x1600 pixels) with only dual-link dvi inputs (1/3 the price Dell/HP/apple sell them direct ebay from South Korea). No scalar asic, but outstanding display quality and helpful to me (double vision < 1 meter distance due to injury). Key term in finding the best was "perfect pixel" and carefully reading each vendor's definition Happy to recommend vendor to anyone interested in similar. Vendor very helpful and LCD's arrived within 5 days of placing order.

Formerly ran a single ATI (before that, a decade of nvidia...) 7750 radeon which drove two older LCDs (hdmi & displayport) with ati-drivers, "single" desktop. under kde, roll around the cube effect, both windows roll, and could drag programs between screens.

New install (due to mandatory 2x dual link dvi) I snagged good deal on pair of 7850 radeons. Each has only one dual link dvi. Performance is impressive

Desktop broken into two separate screens. thus, no dragging windows from one side to the other. Re-configed KDE to put another toolbar, etc on second monitor. Each acts independently.

Now, question for the hardcore video card/opengl/ati-drivers guru When I tried going back to xinerama (versus the failed "amdcccle -- one big desktop", option now missing), KDE 3d effects dissappear. No cube, etc. scoured the web for answers, and found similar folks with libglu and glxinfo problems (and "unknown" 3d accelerator in kinfocenter in the OpenGL listing. all other info points correctly to the AMD/ATI HD 7800 series for rendering and opengl/ES version). Items like glxgears work perfectly, and quite fast with the new card(s), as do the few 3d games I've tried (all single screen).

Verified and performed all the "eselect opengl set ati" , kernel, opencl, bzimage, etc with no luck.

Would like to return to full 3d "one big desktop" as seen with single video card. Tried enabling crossover (didn't work? Didn't help?).

I'm guessing $100+ for an active displayport to dual link DVI connector might do the trick, but that's yet more $$ I'd prefer not to spend since I already have a ton of hardware.

I also did

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equo install --empty kde-meta

just to be sure. Running out of tests and ideas.

Anyone else seen such behavior? Or am I asking too much to enjoy what worked with a single card last week If not, I'll get used to it of course...

Thanks,
andy

[micia]

Hi,

You could try to generate your xorg.conf file directly using the ATI utilities, namely aticonfig, see:

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aticonfig -h | less


for help.

I am not a ATI card guru, as I am not very fond of their support outside of Windows, but I guess what you might be searching for is this portion of the aticonfig command:

5. Multiple display adapters.
List adapters : aticonfig --list-adapters
Init 0 and 2 : aticonfig --adapter=0,2 --initial
Init all : aticonfig --adapter=all --initial
MultiView : aticonfig --xinerama=on

You could experiment with a similar xorg.conf file:

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aticonfig --adapter=all --xinerama=on --initial -o ~/xorg.conf.test


then check the generated file, if it is good try replacing the original xorg.conf and hope it works.

[anomaly65]

Hi micia

Thanks kindly

As soon as xinerama is enabled, all the kde effects disappear, argh..... Prior setup (lower res LCD's, single adapter) was simple dual head setup with amdcccle (control panel) and offered the "big display, single desktop" option for both monitors. Worked like a charm.

I'm thinking the issue is having two video cards.

edit: seems to be a very common problem

Will keep digging. Thanks again!!
andy

[micia]

I'm thinking the issue is having two video cards.

Yes, I suspect that too, that's why I think having the --adapter=all generated configuration into the xorg.conf file might fix something, but I might be wrong, I've never had to setup 2 ATI cards into different displays.

[anomaly65]

Been through a few variations of the "initial" config but with no good luck. I used to hack xorg.conf by hand (and did) but without luck resolving it.

My new high res displays (great displays; much easier on my double vision) need the dual link dvi bandwidth and connectors/cables, which used to come on all sorts of cards "in pairs" but all the current 28nm generation cards have one dual link dvi, maybe a second single link dvi, and various assortments of displayport and/or hdmi.

The two displays work separately with all the 3d (mouse moves between screens, but windows don't), or with xinerama as one (minus the 3d eye candy...argh! looks like gnome or macos from 1987... just fun humor there).

The error kde kicks back is "XComposite and XDamage not available" (both enabled in xorg.conf; work fine without xinerama) and that's tangled up with libglu and all the variations of 3d underpinnings when xinerama turned on, and AMD's variation of nvidia's twinview doesn't appear with two separate cards. I'm pretty sure the crossover and eyefinity features require primary card to handle ALL the video outputs.

thanks again,
andy

[anomaly65]

Hi all,

with 2 cards, and a monitor plugged into each card, "two" X servers run. Mouse will move across, but you can't drag a window.

Solution: Given my hardware requirement for 2x dual link dvi (to support 2560x1600 on each screen), an active mini-display port to dual-link dvi box was needed. Took a gamble, ordered this one:

http://www.monoprice.com/products/product.asp?c_id=104&cp_id=10428&cs_id=1042802&p_id=6904&seq=1&format=2

Both LCD's on primary card. Works like a charm. crossover works as well. Here are the quick steps I did to set that up....

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aticonfig --adapter=all --cfd
aticonfig --add-crossfire-chain --adapter=all
aticonfig --adapter=0,1 --initial


Then an output hopefully should look like so:

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# aticonfig --lsch

Multiple GPU chain for adapter 0, status: Crossfire is enabled
  0. 01:00.0 AMD Radeon HD 7800 Series
  1. 06:00.0 AMD Radeon HD 7800 Series



Then run amdcccle once you're logged into your X environment and configure screens and crossfire as you see fit.

No complaints so far. So, if you're thinking of buying a "direct from South Korea" IPS LCD for 1/3 the price of retail on ebay, sure, check around (worth looking for "perfect pixel" and reading THAT vendor's definition). I did, and am quite happy with my purchase. Most will say "doesn't work with a dvi adapter" which means an active adapter is required, and suggested 2Gbytes of video ram or more highly recommended even for a single screen.

Good luck,
andy

[anomaly65]

a week into it, so far so good.

using the ati-drivers with two video cards, one LCD on each card, essentially you have two good working 3d capable desktops. Mouse moves between them (after using amdcccle to tune to your liking), but apps don't move across the X displays, as they are logically separate. cut-n-paste, etc all work fine, and each X display would rotate, etc independently. xinerama wasn't a good solution and had a few odd side effects IIRC

Have tried a few crossover capable 3d programs, and they seem to work ok. Nothing spectacular, as each card I have performs well enough to not complain much

Main recommendation for high res (e.g. IPS 2560x1600) displays is more video memory is better. Textures and other 3d requirements really prefer the extra memory to work in.

Hope this helps folks. As always, all the sabayon community assistance was excellent and welcomed!
Cheers,
andy