Friends computer works at another friend's house but not hers?

[datfayse]

My brother's girlfriend's computer refuses to get past the ASUS logo while booting at her house, but runs perfectly fine at her friends house. It only works at her house when she swaps out the GPU; it doesn't work when a GTX 760 is in, but will boot perfectly with an old ATI card that only needs PCIe power and no extra cables. She had a cheap power supply but we swapped it with an EVGA 80+ Bronze 600W one and it still doesn't work.

CPU: FX-8120
PSU: 600W 80+ Bronze EVGA
RAM: 4gb (?)
MOBO: Some random ASUS one without a name, 760G chipset
GPU: Works with old ATI card, but not a GTX 760

She's tried clearing CMOS, using a power surge protector power strip, and tried different parts of her house to no avail. Any ideas on what's wrong?

 

[Peter Martin]

good to know because I am seriously considering putting my ancient Lian Li case back into commission with new parts. she's been raided since CPU died after 10 years... lol