radeon r7 260x works in one computer but not another

[valhallarising]

I got a radeon r7 260x sapphire that works in one computer but shows artifacts on windows boot in Another, it runs good in the computer working except for loud fan if not set in amd overdrive.
is artifacts in one computer a sign of something is wrong even if it works in this computer without any sign of problem ? thanks

 

[dangus]

possible that the computer it artifacts on has a power supply that's going south

 

[valhallarising]

could be but i had Another Graphics card in that one running for months without any problems, in the computer that is working now only problem is that ist seems to get hot 80 c under load is that to much or is it safe? thanks