graphics card quit working

Hopefully a quick fix - my graphics card cooling fan started acting up, so I decided to get a new one. I put the new one in, and it seemed not to work. So, I put the old card back in (there was no problem with the graphics, just the fan seemed to be going out) and it didn't work. The fan still turned on, but no signal went to the monitor. I figured I did something to the motherboard, so I bought a new one, and moved all the hardware to a new tower. The card still has the same result - the fan turns on, but no signal to the monitor. I guess my question from this scenario in two parts is - can you fry a graphics card and still have the fan turn on, and without the ability to switch between computers to assess this, how do you know if the card is fried?

Suggestions?

Here are some specs:

Card - XFX PVT84JUDD3 GeForce 8600GT XXX 256MB 128-bit GDDR3 PCI Express x16 SLI Supported Video Card

Mobo (new) - DFI LANPARTY DK P35-T2RS LGA 775 Intel P35 ATX Intel Motherboard
Mobo (old) - ECS NF650iSLIT-A (V1.0) LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard

Thanks!