Alittle over a week ago I defragged my hard drive. EVER since then its been doing one of the following three things after being on the computer for atleast 30 mins.

1) Total reboots without warning.
2)Goes to sleep and can't be woken without warning
3) Freeze for no noticable reason, even when nothing apperars to be running.


I have tried running several anti virus softwares, fixing the registry, Changing firewall software, but nothing seems to work....The provblems happens less if I am not connected to the internet(or atleast it seems too) but as internet is the main use of my computer i cant just stop being connected.

I runn Window 98, MAcaffe Virus Shild, I also tried their Stinger program, and have Armor2Net as my current firewall.....Any ideas would be helpfull.What do the malware scans show? do they detect anything?Everything I have run says that nothing is wrong
mcfee.............headache............r amsticks are........laptop/desktop/tower/pda/try to reformat your hard drive and then install again your OS,, its better to use windows XP OS, but of COURSE BACK up first your files before doing so..Reformating is my last resort right now.....Its a computer with four years worth of stufff on it and I don't have anywhere to STORE the stuff temporarily.    I did try re installing windows but that did nothing.  I was reading something about registry file giving a ghuy a similar problem, but I can't find the site again and the computer froze be fore i could finish reading... has anyone heard of anything like that...How can I check those? I have a registry repair thing, but that pulls up nothing.What type of Power Supply Unit is installed?

Have you tested the RAM?

Store your data and reformat to remove any doubts.

Does your computer freeze when scanning for viruses and the like? If not, keep the virus scanner continiously running so that you can safely back up data.