I have an SLI motherboard, and am running one GTX 560 Ti as main graphics.
I also have an 8800GT Alpha Dog (Zalman) edition hanging around. Could I use this as a dedicated physix processor in the other PCIe slot?
If I can, and I did, would I need to give it the full beans as far as power is concerned? I.E: PCIe power connector also? Or can I leave that disconnected since my GTX 560 Ti already uses the two I have from the power supply....
Main question is, is would this buy me any performance?
The first question is, what Physx games do you plan to play? The reason for that is, sometimes people ask this question and then it turns out they don't play any Physx games.
If you do plan on playing, for example, Batman: Arkham City, Metro 2033, Mafia 2, Dark Void, or Unreal Tournament 3 then the 8800 GT is actually a pretty good dedicated Phyx card. You do not need to connect them with a SLI bridge, but you do need to fully power the card with all the PSU connectors.
You should see roughly a 10-25% performance increase when playing a GPU accelerated Physx game.
It will work as a dedicated Physx card, and you need to install the full PCIE connectors as if it was your primary card, but the 8800 GT is not strong enough for Physx.
Unless you frequently play one of the few games supporting hardware Physx then it's just going to use power and produce heat and not actually do anything for you. It won't use as much power as the main card because most of the time it will just be idling.
What got me thinking about all this was when I ran 3DMARK and I got a remarkably low Physix score. My CPU is a Q6600 overclocked to 3.0GHz. I figured since the CPU had to handle the Physix, that was the reason for my low score.
I hoped the 8800GT would help me out there, and in Physix enabled games. I play a lot of simulation games like driving and flight sims.
I know the 8800GT is a power hog, so if it's not going to do much but drain a load of current from my power supply and create a load of excess heat, then I can't see the point in even trying.
I play a lot of simulation games like driving and flight sims.
As mentioned above, some GPU intensive games such as Mafia II, Batman AC benefit from the GPU Accelerated Physx, any other game that doesn't require Physx won't use the 8800 GT.
Those games you mention don't use Physx, only hardcore and GPU intensive games are much welcomed with the 8800 GT.
besides, the GTX 560ti is good enough to handle a gaming experience with it's integrated Physx engine, so if you care about Power Consumption and Heat issue, just use the GTX 560ti.
To be more specific, many PhysX games do not gain anything from a dedicated PhysX card. Only the games that support "GPU Accelerated PhysX" benefit from it. There are quite a lot more games that support PhysX but not GPU accelerated PhysX than there are ones that do.