I have such a PC here it's a HP D5000T with the C2Q but your post left out make, model, PSU and more details.
The worst part about all this is the age. The CPU is quite old and the system may no longer be able to run without flaws after this many years.
I'd like to give it a go at helping but you left out important details.
Add at a minimum the following.
1. A web report from https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web
2. The machine's PSU make and model.
3. If the machine is a Dell, HP and what model.
4. If you have completed the usual canned air work and heat sink compound replacement (it's that old!)
So im on the fresh installed windows 7 and all, getting random freezes when playing a game for a while, all i noticed that the keyboard lights goes off as well, while frozen.
After that i have to hit restart.
I was checking the temperatures while stress test, got about 70 °C on GPU and also on CPU on the first two cores, the temp of the CPU overall is about 60-65°C max. But had these temps even before for like 1 year without any problem.
Tried to check disk, reinstal windows, memory test and all seems to be okay.
also I didn't find any error in event viewer, except of this WMI error with event ID 10
"Event filter with query "SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA "Win32_Processor" AND TargetInstance.LoadPercentage > 99" could not be reactivated in namespace "//./root/CIMV2" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected."
pc specs: C2Q q6600 2,4Ghz,OC3,2Ghz
8gb Ram dd2
Amd Radeon r7 370 2Gb
(i had the same problem in win 10, that's why i did format and tried win7)
Any else info i can send u guys to help me out? just ask.