Just a thought. A GTX 760 uses auxilary power connectros, and as far as I know, the X51 PSU doesn't support a GPU that demands as much power as a 760. That would mean a bigger PSU that would end up having to be an ATX PSU, which won't fit in the X51 case and so a new case would be needed. Also, i don't think a 760 would fit in that case anyway. I maybe wrong, but I don't think it'll work without more money being spent on a new PSU and new case