BioShock 2 Ambient Occlusion kills framerate but not GPU usage -- 580!

[fixbsod]

I installed the new Geforce WHQL drivers this weekend and wanted to try out some of that cool Ambient Occlusion stuff. Skyrim was a no go as I had tweaked all my INI settings and so I put that away as I wasn't up for 20+ mins of messing with settings. It did work but seemed a little too laggy but I was able to see my GPU maxing out @ 99%+

Seeing as I have a fairly state of the art system -- i7-2700k @ 3.9ghz, 16GB RAM, evga 580 1.5gb, w7 64bit I wanted to try some BioShock 2 using AO. I was able to force AO using the nvidia control panel but my FPS took a DUMP (20?). I tried dropping the res from 1920x1080 and still very low FPS. However, when I checked GPU usage it was in the mid 40s!! Took out the AO and FPS back up. Soooo...is this just an issue with BS2 ? The game was not CPU limited as that too was in the low usage...what gives?

I'd like to try AO on some other games but as it appears there is more to it than just clicking the control panel I thought I'd ask for advice before messing with other settings...

 

[blackened23]

You have to understand that using override is a last restort and you shouldn't generally use it. Bioshock 2 AO will not work. The engine is an old outdated piece of crap, it doesn't even have native AA.

Enabling AA or AO in games that don't natively support it with the "override" feature will kill your framerate in most games. You should never, ever, ever, use override unless its absolutely necessary.
Hell even borderlands 2 chokes with override AA on the 580. (at 2560x1600)

Point is don't use override.

 

[fixbsod]

I know native support is best, but I am scratching my head on the underutilized gpu + cpu that accompanies the stuttering. And I have been able to enable AA with BS2 without any obvious fps hit thru the nvidia control panel.

 

[notty22]

I believe one difference in this driver version is there are 2 settings for forcing AO. Performance and quality.
Have you tried performance.

 

[blackened23]

I know native support is best, but I am scratching my head on the underutilized gpu + cpu that accompanies the stuttering. And I have been able to enable AA with BS2 without any obvious fps hit thru the nvidia control panel.

I had the same issue with Bioshock 2, although I never tried AO. I used 32x CSAA (on sli 580s) and at 2560 resolution it lowered the framerate rather signifigantly. I don't think the engine handles it well.

Override IQ works decent in some Unreal engine games, but bioshock 2 definitely is not one of them.