I have a computer with the following specs:
Pentium 4, 2.6Ghz
1Gb DDR RAM
120 Gb Hard Drive
Windows XP Home Edition with Service Pack 2
I have had it for 3 years, and everything was fine.
Then suddenly, there was a big thunderstorm close to where I live, and even though nothing in my house seems to be affected, my computer has developed faults since that time.
The fault is that it freezes all the time, and not just hanging, it properly freezes. Control-Alt-Del doesn't work, the mouse or keyboard won't work, and pressing the NumLock button doesn't turn on the NumLock light. It's really weird. My only solution is to turn off the power and turn it back on.
I have tried to make it freeze so I can try and pinpoint the cause, but I couldn't. The only thing I noticed was that if I logged into Windows and left it (opened no programs, etc), it froze after about an hour. However, if I started using it, by loading stuff such as the internet or Word, it would freeze after about 5 minutes.
Because of the storm, I thought it might be a power problem, and I tend to leave my machine on 24/7 sometimes, so I took out my existing 300W power supply, and replaced it with a 550W one.
The freezing problem remained.
I then thought that since it seemed to freeze quicker when I loaded up programs, it might be a RAM problem, so I installed and ran this program called MemTest86 and my friend warned me that it might take about 50 hours to complete so I left it running, and it froze after 13 hours. Since it froze, I thought it might be a RAM problem for sure, so I replaced both my 512Mb RAM sticks with 2 new ones, but the freezing problem remained.
I then thought it might be spyware or a virus, so I scanned my system using AVG Anti-Virus Free Edition but it froze half way through. I booted into Safe Mode, and ran the anti-virus program and it completed but found nothing. I ran Lavasoft Ad-Aware Free Edition and Spybot Search and Destroy (both in Safe Mode) and they both found nothing more than cookies. I cleared everything it found though, and booted back into normal Windows but the freezing problem remained.
I tried to scan for hard drive problems using chkdsk, which ran a scanning tool when I restarted my machine, and that scanning tool completed without finding any faults.
I then decided to do the drastic thing and reinstall Windows, so I did and chose the Quick Format using NTFS, and everything reinstalled fine (including Service Pack 2 from a CD), but once I had Windows up and running, it froze again.
I then thought it might be a problem with some hardware, such as the broadband modem, keyboard or mouse, so I reinstalled Windows for a second time, and didn't connect my modem and connected a different keyboard and mouse, but again, it froze once it was up and running.
I was getting frustrated so decided to reinstall Windows one last time, and to not install Service Pack 2 in case that was the problem, and during the reinstallation process, I decided to choose Format using NTFS (not the Quick Format one but the other one), and the computer froze half way through, at about 53%.
I was quite confused, as it had never froze at this point before, so I went onto Google (on my laptop), and looked into the differences between Quick Format and the other Format and it seems the difference is that Quick Format doesn't scan for bad sectors.
So, since it froze during the normal format (non quick one), I thought it might be a hard drive problem, but wouldn't the chkdsk tool have spotted these and fixed them?
I am a little hesitant about replacing my hard drive because a) I don't know how to replace them and b) Buying a new 100Gb+ hard drive might be expensive, especially if it doesn't cure the problem.
Has anyone got any ideas what might be the problem?
A few of my friends mentioned things like cleaning my heatsink (but I don't know how, or even what a heatsink is), or a faulty power supply might have fried some soldered-on components so it won't ever work properly, and stuff like that. Graphics card problems were also mentioned, and that might explain why it seemed to work in Safe Mode (although I only waited an hour in Safe Mode, it might have frozen afterwards for all I know). How can I test my graphics card for problems - using the Device Manager, there seems to be no problems reported).
My friends aren't really experts though.
Any advice/suggestions would be appreciated and would save me buying a whole new machine!