PC turns off after couple seconds

[AKTAL]

hello all,

recently ive taken apart my old desktop, cleaned the cpu heatsink from all the dusk, and put on some new thermal paste. the reason for that is my pc would sometimes shutdown without any notice or warning, so i decided to clean the heatsink in case it was overheating. after finishing the procedure i turned on the pc. at first, everything seemed to be working fine and all the fans are spinning and such, but after about 5 seconds the entire system shutdown along with the fans, and a semi-quiet high pitched sound starts from the CPU/RAM/PSU area (sorry, best way i can describe it). so the bottom line is; would you say that there is something wrong with the power supply?

any help would be greatly appreciated

 

[amuffin]

Thsi definitly sounds like a bad psu.

 

[Z1NONLY]

Is it on long enough to check CPU temps in the BIOS?

 

[kcsmacker]

Sounds like both the random shutdowns and what happened after was caused by the power supply. Do you have a spare that you could test to see if that is the case?

 

[AKTAL]

its not on long enough to check cpu temp, but its usually around 50C. The shutdowns have been happening for the past couple months, so would you think that this is a coincidence? That the one time i take off my cpu, the power supply stops working?

 

[andrey64]

its not on long enough to check cpu temp, but its usually around 50C. The shutdowns have been happening for the past couple months, so would you think that this is a coincidence? That the one time i take off my cpu, the power supply stops working?

best bet would be find a spare psu and plug it in. if it powers on and keeps on then check all your bios settings. Just reset your bios settings and try to restart it again. if all works then BAM you found your issue.