BleepingComputer.com: Windows XP hangs, not responding, freezing etc

I am fixing a HP Pavilion a1300 Desktop PC series. It is running XP and has 1GB of RAM. It did have a virus on it and was going really slow. I removed the virus and have run AVG, Malwarebytes, SAS and they all come up clean. I have done disk clean -up, defrag, removed cookies and temp files etc.. It seems to be running noticeably better, except for one thing. It just hangs and you can't do anything. It will say not responding and sometimes it's browsing and sometimes it's when I am not on the Internet. Sometimes it won't allow me to close a program and I have to press alt/control/delete. This problem is extremely frustrating and would like to fix this issue before returning the ladies PC. The system is very dirty with dust everywhere, therefore I will clean that out. I have viewed the event viewer, but it's just hard to understand the errors and what they mean. There is tons of HP Games on the PC. It also takes longer than usual to download software. Can someone tell me how this problem is caused and what to do to fix it? Thanks

Try cleaning it up good first. Paying particular attention to the processor heat sink and fan as well as the power supply fan.

See if that does not give a noticeable boost. What you are describing are classic overheating symptoms.

You say it was it this slow prior to cleaning the infection, has it improved any?

ThunderZ, Thanks for the reply. It has definitely improved the speed of the system. The only issue now is the freezing, not responding and it won't close sometimes. I will give it a good cleaning tonight and get back to you.

You may want to post over on the Am I infected board as well. Just to get a final good bill of health.

Thanks for the good advice. I cleaned out the entire inside of the PC and that seemed to really make a difference.

Heat kills.

A lot of users have no idea that the inside of the cases need cleaned every once in a while, depending on their environment.

Glad it seems to have helped.