Going SLi

[CaNNsA]

Current rig is:-
i7 930 @ 3Ghz
12Gb t/c RAM
1Gb GTX560 Ti Twin Frozr

Just bought the 2Gb version on ebay.
The plan is to have the 2Gb as the primary card and bump Physx onto the secondary (1Gb) card.

That should be ok right?

[Goku]

What do you have for a PSU?

To be honest I'm confused from this purchase. A 560 Ti doesn't have the power to drive 2GB of VRAM. On top of that you only have a 1GB version currently making you only able to use 1GB on both cards if you want to do SLI. I'm not totally sure how much of a added benefit you will even see from having PhysX set to a dedicated card either vs just running PhysX with the two in SLI already. You will have to experiment with that anyway.

Be fun messing with your new card at least.

[CaNNsA]

From what I heard, and read, only the ram on the primary card is used so I dont think I will be limited to 1Gb.

PSU is a 750w OCZ.

How is the GTX560ti lacking in grunt for 2gb of vram?

[Goku]

No that is not the case. When using SLI what is being stored on the cards ram is identical to both cards. Therefore you are limited to 1GB usable VRAM despite having 2GB on another card. I never heard anything like what you have heard or read either.

The GTX 560 Ti simply does not have enough GPU power to push 2GB of VRAM. The card will be running awfully low FPS with a game that is probably using that much VRAM. Even in SLI the setup doesn't have the proper processing power to make use of 2GB of VRAM either. Sure maybe if you are looking at higher end cards these days you probably will have a actual need for 2GB of VRAM to not limit the GPU.

[CaNNsA]

Righto,

Installed the 2gb as the pri card, used some modded drivers to get the 2 working in Sli.
You are indeed correct sir, I am using 1gb on each card.

No biggie though as my fps is stable and limited to 30 with physx enabled @ 1080p.

Its all good batman