Odd OC problem

[demien88]

So I powered on pc this morning to be greeted with hard reset after few seconds I let it boot up normally. Once inside windows I noticed some cores have gone down to 1.4 ghz. Now I wouldn't be so surprised if OC wasn't stable but it survived one hour in prime 95 with some minor fluctuations in speed about 50mhz up and down. This only happend when I was setting up OC for the first time, it was set on 4.3 for about 6 months before this happend so thats why its so strange.
I fixed this speed lock by changing vcore a bit saving then entering bios again and setting vcore as it was before.
Should I be worried? What could go wrong BIOS, PSU, OC itself?

 

[Johan45]

Could be something with the PSU or the board or just a crappy windows update. Just keep an eye on things. If it persists then it'll need to be routed out.

 

[demien88]

It happend even during summer when it was at 4.2 with or without hard reset same "fix". How to be sure which component is causing this?

 

[trents]

Could be a bad driver. If a blue screen was involved then install the free program, "Who Crashed." It can provide some general guidance as to the reason for the blue screens.

 

[demien88]

No BSOD of any sort no errors nothing, it happens on startup of machine second after i press power, and thats it later like nothing happend after said "fix"