It would support if it has a PCI-express 2.0 x16 slot, newer
boards like urs should have.
One other thing is you must have a pci express 6pin or 8pin(or
both)connector that can be readily connect the power supply to ur
graphics card, if you do not have it, make sure that the graphics
card comes with a 6pin or 8pin(or both) to molex connector.
Some graphic card use two 6pin or one 6pin and one
8pin connector, im nt sure whether ur 8800gts uses which, you also
need to make sure that ur power supply can draw enough power( not
peak power) to supply the graphics card
My 1st 3870x2 uses 1 6pin and 1 8pin pci express power
connecter, and my 2nd 3870x2 grahpics card uses two 6pin
connecter