I have an older laptop with an ATI 7970m graphics card in it and I'm having tons of issues. I can buy a new card on eBay easy enough, but... can anyone think of a way for me to test whether it is the card itself or the Motherboard of the laptop... or even power supply? I don't want to invest $250 on a new mobile card and have the issue be the unfixable motherboard.
Since you did not list what these "tons of issues" actually are, hard to say what you can test or how.
Need full details of what is happening, when it started, what happened before it started if anything, what you tried already, and full specs of the system.