24A@12V is roughly equivalent to 2.6A@110V
A*V=W

There are many reasons your system is doing this. If it is stable enough to check the bios settings of the RAM, Bus, processor, etc; then do that. I always suspect the PSU first. I don't know why....

I have always relied on the replace with known good, theory. I take the suspect video card, put it into a working computer. Does it work? check. Take the PSU from the working computer, use it to power the broken computer. Did that fix the problem? and so on....