Sli performance is unchanged over build 300 using Nvidia driver 327.23. Still approximately 9-10 fps with HDR on at Brianza with settings identical to build 300 sli performance post. Same performance with road and environmental reflections enabled. Charts to follow. Build 342 has a CTD under Windows 8.1 using Nvidia drivers 331.58 and 331.60. Driver 327.23 continues to work correctly but all fonts, windows and icons are magnified in every application including rF2. With no changes to sli compatibility bits in the rF2 profile included in the Nvidia drivers for some number of build revisions now, multi-gpu sli performance has degraded with each release so far. There do not appear to be any 3-way sli specific profiles. 3 x EVGA SC Titans i7 3770K @ 4.6GHz 16 GB DDR3-2666Mhz
Hi otta56, I agree that Sli, Sli/multiview & sli/multiview/HDR are far from optimised on rf2 but running Nvidia Drivers 331.65 & not a single CTD. However, the magnified icons was something I experienced when I upgraded from W8 to W8.1. What I ended up doing was uninstalling my Nvidia drivers - Using Driver Sweep to clear up the residue - Boot W8.1 in Safe Mode - use Driver Sweep again to remove the rest of the entries - Boot W8.1 & installed Nvidia drivers. Since then switching between screens didn't result in large icons and just some general strange behaviour I was experiencing after the 8.1 update.
nVidia posted 8.1 drivers, I would update. For now, I think disabling SLI is the only thing I can say to do.
Thanks for your suggestions Tim and Magus. I will try a clean install of Nvidia driver version 331.65 again. Most of the problems I had with the original install are mirrored in comments by other users in the Nvidia forums for these drivers. With Surround enabled there are lots of cursor freezes and generally unresponsive applications. This may not be the case with single screen (non surround) installs. Hopefully Nvidia will spend some time tuning the profile compatibility bits at some point. The lack of a 3 card sli profile does prevent the software from reaching its full potential. Btw, an end-user developed Nvidia driver removal tool DDU does an excellent job of removing all residual Nvidia drivers without having to boot to safe mode. I have used it for the last three driver version upgrades without incident. It can be found here: https://forums.geforce.com/default/topic/550192/geforce-drivers/display-driver-uninstaller-ddu-v9-1/
Do you mind me asking what you consider to be "disabling SLI"? As in, setting rF2 to "single-GPU" mode in the Nvidia control panel, disabling SLI overall or even physically removing the graphics card? Probably not the last but I tough I'd ask anyway ^_^
An update on this. After a clean install of Nvidia driver 331.65, the CTD for build 342 persists. It appears to be a code change to Nvidia Surround that causes the problem. Build 342 is fine in single screen mode (maximize 3d performance setting in the Nvidia control panel). Unfortunately, this means no triple screen with multiview for the time being, at least in my instance. Using 3 x sli on one screen does allow all settings to be run at maximum with HDR on at 2560x1440. Turning HDR on reduces framerates by more than half on all tracks tested with Limerock Park dropping from 65 fps to 29-35 fps depending on the section of the course. Brianza is similar dropping from 65+ fps to 30-36 fps depending on the section of the course.
Did you do a clean install of the drivers after using the DDU tool you linked? Have your tried uninstalling the divers (& physx etc) then using Driver Sweep & again in Safe Mode Boot just to be certain? Sorry if all this sounds obvious, but I take it you have definitely set up the connection properly as stipulated on the nvidia site for triple sli 2d gaming. If you are going single screen then there are these 2 threads with some information: 1. Nvidia SLI - Possible big framerate improvement. 2. 4x Better Graphics and way more FPS Guide
Yes the cards are correctly set up. Also read through the guides. Most installs appear to be single card, single screen. The multi-card, triple screen setup with multiview enabled I am using did not unfortunately benefit from the tips offered in these threads. Changes to the stock sli compatibility bits actually lowered the existing frame-rates in my case. The single screen results are only to test the performance of the cards prior to an Oculus Rift 4K release some time in the next calender year. Performance without HDR or reflections enabled (65+ fps in multiview @ 8020x1440 triple screen) indicates that rF2 code needs optimization for multi-gpu installs. The fact that single screen performance with HDR & reflections on is in the 35-40fps range indicates that existing graphics issues which are obvious at higher resolutions are simply being hidden by the power of many graphics card installs at lower resolutions. Stuttering is a case in point. It is very obvious at the higher resolutions offered by triple screens but is still there on single screens, just much less noticeable. The answer to this should be to tune the code not lower the settings. Perhaps, as Tim mentioned, some testing on multi-gpu, triple screen machines would help identify places for improvement.
I wonder if that's a 3-way SLI issue. This build scales well with my 2-way SLI triple monitor setup (I always use multiview) and I see about an 75% performance increase from one card to two and I've never had a CTD in this build or the last 5 or 6 builds. My only issue is the crippling perfomance hit of multiview + HDR.
It's very likely. The sli compatibility bits are really only tuned for two cards. Although each driver release says it supports 3 and 4 way sli, the rf1 and rf2 profiles have 2 way support only in the compatibility bits code. The third card generally shows less load than the other two in monitoring software.
IMHO we now have big enough cards not to sli. IMHO waste of $$$ on 2nd card, yes i used sli 560 ti b4 going to a big card gtx 680 4gig
But for some, like myself, a single card just doesn't suffice as I have 5 monitors working off one pc (sometimes 6) two for work on a desk & 3 over on a racing rig with playseat. Even now, with Sli broken worsening my performance I'm forced (through convenience) to use it as I don't wish to keep switching the position of cables on the GPU & at the same time want to keep the option of sli if I game anything other than on the racing rig. Once it's fixed & can enable HDR, I'll be a happy man.
