computer start for split second and turn off immediately

[jaykpatel304]

i have old build with amd fx 6300 with shapphire hd 7770. The first i thought it was psu problem then i put for replacement they replaced with new one then i installed new psu still same happend.
After troubleshooting i found i have problem in gpu. If i unplug external gpu and use old gpu then computer start normally. so i put for replacement they denied to replace because of rust on 4 screw. now i have no option. can any tell me what to do?

 

[ss202sl]

get a new GPU

 

[junii421]

get a new GPU

GPU is not the problem, try to take out everything, keep in 1 stick of ram and the cpu, then try to boot if doesnt work, try the other stick of ram assuming you have 2. try to boot that, if it doesnt work i have some other solutions.

 

[jaykpatel304]

get a new GPU

GPU is not the problem, try to take out everything, keep in 1 stick of ram and the cpu, then try to boot if doesnt work, try the other stick of ram assuming you have 2. try to boot that, if it doesnt work i have some other solutions.

i have only 1 stick of 4 gb. computer boots only if i remove my hd7770.