Sager NP9262: Two different types of Video cards installed?

I have a Sager Np9262 with a GeForce 9800m GT video card that seems to be dying. I am currently in the process of buying a used card that is compatible with the np9262. I am able to use my np9262 right now because I have it underclocked. My question is once I receive a replacement card (it will be a different card then I have now) can I have both cards installed in my system and using them both at once since they are different? I have seen people say they use one video card for one thing and the other only for physx or something. Not sure how that works but I figure if that is possible maybe I could assign my current card to something that doesn't require a lot of power and keep it underclocked to still get some use out of it, while using the new card for almost everything else. Is this not logical? I am obviously not an expert in this area.

 

You can install two p398 G92 cards on NP9262 and form SLI.

8800MGTX/9800MGT/9800MGTX: SLI
FX3600M/FX3700M/GTX260M MXM2.1/GTX280M MXM2.1: Non-Bridged SLI

1.Flash same vbios(9800MGT or 9800MGTX) to both cards.
2.Reinstall the driver.
3.Enable coolbits in case they have different amount of vram(e.g. 512MB vs 1GB)
4.Enable SLI in NV control panel.

 

Ok, I have a 9800m GT, a Quadro FX 3700m and a Quadro FX 2700m, my 9800m GT was causing a lot of problems so not sure if I could still even use the card, but anyways, is there a way I can make use of two of these 3 cards in my np9262, even if they are not "sli" (like just having two video cards installed but not connected)? I just don't want to waste any potential I have, and since I have two quadro cards I figured maybe I could combine them to get some better performance, or I figure maybe I can change the vbios of the 9800m GT, or bake it, then have it alongside the 3700m but only use it to play games. Any thoughts?