That's an old piece of iron. But I owned 2 at one time, now down to a single d5000t HP core2quad.
-> Start with a deep clean of the insides. Then pop off the CPU cooler to wipe off the old compound and apply fresh. While the cooler is off give the fins a good blast of canned air and swab clean.
Button it up but leave the case cover off.
Our last 2 core2quads got this treatment and run well under load. But at that age it's not a sure thing.
Both are running Windows 10 Pro because... they came with W7 Pro.
Hello! So, ive looked all over and cant find anything, so i came to smarter people in the community. After talking to 20+ microsoft assistants and no help, ive tried to fix myself. My current setup is:
GPU:nvidia gtx 1060 6gb
PCU:intel core q6600
Motherboard:xfx 750i
8gb of ddr2
When i play games, i get perfect fps and settings that i like. As i progress, after a few minutes it freezes. Basically, mouse and keyboard still work, and control, alt, delete still works. Ive tried almost everything, including reset and updating drivers. If you click control, alt, delete the wifi symbol has a frozen loading sign. And on the desktop, if you hover over an icon in the taskbar, there is no light that indicates your cursor is over it. I have noticed the audit events have been dropped by the transport. 0. Finally, this all happened after upgrading to windows 10 from 7. No problems (from what i saw) on windows 7. Also i have not overclocked any parts.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic