The most common is the slow speed of CPU fan, which leads to CPU protection due to poor heat dissipation, followed by poor contact of memory chips, or poor performance of memory chips, which leads to a decline in power supply capacity. Rare is the poor performance of graphics cards.

I suggest you check the CPU fan, power supply, memory and graphics card first. If there is no problem, it is the motherboard.

Secondly:

1. Hardware failure, such as bad hard disk, overheated cpu, insufficient memory, etc. (Scan hard disk, check CPU fan, add memory)

Second, soft fault: If your computer runs for a long time after installing the system, running and installing applications repeatedly in this way will increase a lot of registry garbage, temporary file garbage and hard disk fragments, which will slow down the system.

Third, viruses and Trojans will also slow down the system a lot. Just because you didn't find it with anti-virus software doesn't mean that your computer is virus-free. The relationship between virus and antivirus software is spear and shield, and it has been changing!

Suggestion: If there is a GHOST image, it is recommended that you restore to the system when you first installed it. If not, reinstall the system, make a ghost image, and restore it if necessary.