Unabashed GFX Noob asks naive question

[BonzaiDuck]

I've already said this in other posts: I've built an SLI rig only once before and Haven't bother much with graphics overclocking. I always thought the details of "Manage 3D graphics" seemed a bit . . . arcane . . . I'm learning -- slowly.

I posted a thread in the gaming forum, but I don't think the answers there are forthcoming.

First -- I've discovered that certain types of video errors, sometimes with symptoms of "graphics driver failed and recovered," borked configuration of Media Center and other things will upset the power-saving feature of my 970 cards. It all settles out if you disable then re-enable SLI: the core and memory clocks return to their low-end levels.

Second -- and here comes the question -- I installed the Steam Assetto Corsa Racing Simulator. It had worked flawlessly on my other system with a GTX 780 card. On the 2x 970 SLI system, once you hit the "drive" button within the software, the screen blanks and the monitor returns the "out of range" message -- as if you'd selected a refresh rate too high. This also borks the power-saving clock level for SLI.

I finally discovered that turning off "full screen rendering" within Assetto Corsa makes the problem go away.

What the hell is "full screen rendering?"

 

[AntonioHG]

Sounds like you need to wipe those drivers and install them fresh. You shouldn't have any random driver crashes and buggy idling clocks.

Use DDU: http://www.wagnardmobile.com/DDU/

Full Screen Rendering is the game running maximized with DWM disabled. IE not in a window.


Edit:

Also, do you have any overclocking software like Afterburner or EVGA Precision installed? Maybe your processor is overclocked..? Those could cause some issues at times. Return those to default too.

 

[EightySix Four]

The idling clocks are a known issue with 970's in SLI, it was posted about on here the other day.

 

[BonzaiDuck]

The idling clocks are a known issue with 970's in SLI, it was posted about on here the other day.

It could have been a post by yours truly!! I know when I posted the thread, folks were speculating about it and there wasn't any reference to previous observations of the same kind. But I don't want to flatter myself.

All I can say is that whatever causes it to happen on my system so far are all things you'd want to avoid anyway.

For instance, I'd misconfigured Media Center for my HDHR'. I would select an encrypted HD channel, MC's spinning wheel would keep spinning and spinning, and eventually I'd have to exit MC by choosing "close" or the "X" box several times. Especially, if I had to terminate the program through Task Manager, it would also bork the SLI'd clock speeds for the 970s. Once MC and the HDHR' were set up and activated properly, these sorts of episodes disappeared.

Similarly this problem of the Assetto Corsa simulator. If these things are avoided, there's no erratic behavior in the 970s or their driver.

I went through this driver installation mess, also. You're best to do a "clean" installation for the NVidia drivers, and that was true for my 570 card, my 780 card and these 970's as well.

It's possible that version 347.52 fixed some things, and there was a rumor to that effect. I expect more revisions from NVidia.

ADDITIONAL THOUGHTS:

The peculiar thing about the Assetto Corsa simulator is this. When I turn off "fullscreen rendering," that game still loads in full screen mode. I think it's possible this is a software problem.

As to the overclocking, that TOO could be the problem, but I doubt it. The cards are capable of pushing the core clock higher than 1500, but these are only running at 1440. Memory clock is capable of 4,000 (8,000) Mhz, but I'm only pushing it to 3,750 (7,500).

None of these anomalies causes BSODs, and I stress tested for several hours. Instead, I have another suspected source of a BSOD or reset that only occurs every 7 to 10 days. I can reset the cards, but that problem persists, and it's the same problem I had last year with the sig-rig. That system no longer shows these occasional (VER-RY occasional!) resets. I have suspicions about the onboard Marvell SATA controller. It's currently enabled, and the problems with the sig-rig disappeared when I disabled that controller.

 

[Flapdrol1337]

Run on stock clocks when troubleshooting, saves you trouble

Anyway, in assetto corsa you can select resolution as well as hz, if the hz is not supported by the monitor you'd get this "out of range" behaviour. If you don't choose fullscreen it will of course not be a problem as the game will be running in a window (but at fullscreen size), this will add latency though.

 

[BonzaiDuck]

Run on stock clocks when troubleshooting, saves you trouble

Anyway, in assetto corsa you can select resolution as well as hz, if the hz is not supported by the monitor you'd get this "out of range" behaviour. If you don't choose fullscreen it will of course not be a problem as the game will be running in a window (but at fullscreen size), this will add latency though.

Thanks. I've said elsewhere in the forums -- perhaps yesterday -- that the card's quirky power-saving behavior was due to software settings, incorrect configuration of other hardware and software, or simply using the VGA analog ports of an old KVM. The stop-code 124's, though, seem likely to have been caused by the over-clock, but I need to test further. That symptom might still have been caused by the other possible causes, or interaction with the possible cause of the OC setting.

All I can say is this: all my little problems seem to have disappeared by using my monitor's HDMI port with a bi-directional HDMI switch supplementing the old KVM -- and of course, the software tweaks.

ALSO -- I posted the following thread in the HTPC forum, but it really belonged over here in Vid&Gfx. I may have been the source of a rumor that the GTX 970's power-management was "flakey:"

http://forums.anandtech.com/showthread.php?t=2422503