I will be the first to admit I don't really know much about computer's but I can get by. This problem has baffled me and even friends who work as PC technicians. So this is my last try at finding out if anyone knows.

A few days ago I was on my PC in the evening, everything was working as it should. my anti-virus started its scan as it does, but as I was doing other things i canceled the scan. The next morning, as I wouldn't be using it, I turn my PC on and leave the virus scanner to run. I use Symantec, Defender and also Spybot. None of these found anything on my PC so I turned it off. Came back that evening and within about a minute of booting up my PC now freezes completely. This happens whether I or anyone else logs onto their account or not. As it was a sudden thing I thought it might be hardware issue but the PC will still run in safe mode, where running the virus scanners etc still finds nothing. As a last attempt i did a system restore to a few days earlier to when I knew my PC was running fine and my PC worked fine again, until yesterday where it started crashing int he same manner as before.

I use Windows XP service pack 2. I can't remember off the top of my head my system specs but if they are needed I will find them out and add them.


Short of re installing all of windows I am at a loss, if anyone can think of anything I would be very grateful.

Thanks, Greboth.

Freezes - Does it recover? Does the sound "loop"? Does the screen lockup or just go blank? Does the HDD light do *anything* while it's frozen?

If you happened to know whats your PSU?

Quote from Jakg :

Freezes - Does it recover? Does the sound "loop"? Does the screen lockup or just go blank? Does the HDD light do *anything* while it's frozen?

If you happened to know whats your PSU?

No once my pc has frozen it doesn't recover. Never had any sound playing to know if it loops. The screen just locks up, whatever is on screen just freezes completely. I am pretty sure HDD light doesn't do anything when it is frozen. I can't check right now but I will find out when I can. I will also find out my PSU too. Although I have changed no hardware and the case hasn't been opened in a few weeks.

Also just incase it is important, watching my cpu usage it doesnt spike before the freeze, in fact it islow, with cpu usage being about 5%. Short of timing it with a stop watch the freezes happen at the same time everytime.

is there *any* correlation between when it freezes and what your doing? Does giving it alot of work (ie a game) accelerate the lock up?

Could it be getting really dusty and thus hot? the heatsink could be full of dust

System specs
AMD Athlon 64 Processor 3000+
WinFast PX6200 TC GeForce 6200 TurboCache 128 MB
512 MB RAM
300 W PSU

Windows XP service pack 2.

To answer the hdd question previous, the hdd lights comes on but as soon as the pc has frozen/locked up its goes off.

As for something I am doing and the lock up, the lock up happens whatever I do or don't do. If i just turn my PC on, xp loads and the login screen appears, If i leave it it will lock up, If i or any other user logs in the lock up happens also. So it seems completely irrelevant of what is being done as the lock up happens within about 30 seconds - 1 minute everytime.
It could be getting too hot but, looking at this logically, I don't see it being the answer as the lock ups happened, after a system restore the pc ran for around 7 hours under varying load. Then the lock up's happened again, and happen after the same time. Also I have had it running in safe mode for a few hours with no problem either. I will have a look though for dust and clean the heatsink if dusty.

300W PSU?

What brand is it?

Sounds like it could be that.

System Restore puts a lot of load on the HDD's, not the CPU - but if it happens in 30-60 secs loading a game wont really say if it's sped it up or not.

I'm a hardware geek and i'd blame the PSU, but the fact System Restore didn't make it keel over is.... suspicious.

Devil?

Generally those symptoms aren't related to software: it could be a failing power supply or (more often) a bad RAM module, even a mobo failure (I had this problem on a mobo with condensers leaking brownish stuff). If you're able to boot in safe mode, do some stress tests. Start with a torture test with Prime95, doing at least some cycles. This will test only your CPU and your RAM. If it fails doing it job and halts you could have some bad RAM. You can also try Memtest86, but sometimes it fails to discover some issues: but at least, if it shows some errors, you most likely have some faulty RAM, so you can test some other modules and see if they're fine. Prime95 is a bit more picky, but it cannot identify the problem, it just shows you have one (CPU? Mobo? RAM?). Then use some more general benchmarks that test your hardware. Use HDTune to test both health and performance of your hard disk. Check voltage stability of your power supply, if you can compare voltages with suggested values.
Generally, however, it is a good idea to test hardware without running the OS on your hard disk: prepare (or have someone prepare it for you) an UBCD for Windows, most diagnostic tests are already there: it's useful and not time consuming. The GPU is the only component that may need a test with your original OS.
On the software side, you could have some nasty rootkitted software. I can't tell you how to look for rootkits since it's a job that requires some OS knowledge, but anyway if you look for some anti-rootkits you'll find them on the net. You MUST know how to use them anyway, so I won't enter the discussion. My favourite one, however, is GMER. And, absolutely, ditch Task Manager in favour of Process Explorer, and get a serious antivirus. Symantec is evil. If you have some suspects about a single file, virusscan.jotti.org is what you need, but it's sometimes very busy, so you have to wait in line. Otherwise go for housecall.trendmicro.com or other online scans (like Panda) for a faster job.

Quote from Jakg :

300W PSU?

What brand is it?

Sounds like it could be that.

System Restore puts a lot of load on the HDD's, not the CPU - but if it happens in 30-60 secs loading a game wont really say if it's sped it up or not.

I'm a hardware geek and i'd blame the PSU, but the fact System Restore didn't make it keel over is.... suspicious.

Devil?

Yes 300W, as for who makes it I would guess Novatech as i bought the pc ready built from them and it doesn't have a brand logo on it. So either Novatech or some other generic one.
I did the system restore to go back to before the problem started to see if it got it working again which it did, not to test out hardware.
After talking to another friend who works in the pc field he suggested it could be a faulty driver update which automatically updated itself, which system restore rolled back to before it auto installed and then it automatically installed itself again causing the problem. Which he said would also explain why it runs in safe mode as it doesn't load all the drivers. No idea if this is plausible but anything is worth a try lol.

Quote from Albieg :

Generally those symptoms aren't related to software: it could be a failing power supply or (more often) a bad RAM module, even a mobo failure (I had this problem on a mobo with condensers leaking brownish stuff). If you're able to boot in safe mode, do some stress tests. Start with a torture test with Prime95, doing at least some cycles. This will test only your CPU and your RAM. If it fails doing it job and halts you could have some bad RAM. You can also try Memtest86, but sometimes it fails to discover some issues: but at least, if it shows some errors, you most likely have some faulty RAM, so you can test some other modules and see if they're fine. Prime95 is a bit more picky, but it cannot identify the problem, it just shows you have one (CPU? Mobo? RAM?). Then use some more general benchmarks that test your hardware. Use HDTune to test both health and performance of your hard disk. Check voltage stability of your power supply, if you can compare voltages with suggested values.
Generally, however, it is a good idea to test hardware without running the OS on your hard disk: prepare (or have someone prepare it for you) an UBCD for Windows, most diagnostic tests are already there: it's useful and not time consuming. The GPU is the only component that may need a test with your original OS.
On the software side, you could have some nasty rootkitted software. I can't tell you how to look for rootkits since it's a job that requires some OS knowledge, but anyway if you look for some anti-rootkits you'll find them on the net. You MUST know how to use them anyway, so I won't enter the discussion. My favourite one, however, is GMER. And, absolutely, ditch Task Manager in favour of Process Explorer, and get a serious antivirus. Symantec is evil. If you have some suspects about a single file, virusscan.jotti.org is what you need, but it's sometimes very busy, so you have to wait in line. Otherwise go for housecall.trendmicro.com or other online scans (like Panda) for a faster job.

I am busy today, but I will try those as soon as i can

Thanks for all your help so far guys

Have you made a log file with Hijackthis already?

Quote from Jakg :

Could it be getting really dusty and thus hot? the heatsink could be full of dust

Only time my pc ever froze on me was overheating on the graphics card - odd that, frozen and overheating. But it was very very dusty. i switched off, vacced and brushed all the dust bunnies away and half the hair from a dead rodent, it seemed, then I stopped overclocking my GPU and all was fine again. Exccept the rodent, that was beyond help.
All the dust has accumulated in the fan section of the GPU heatsink.

I've done the same thing with my PC, i moved my desk, turned it on, glanced at the CPU temp in my taskbar and it read "80°", i thought "Ok, SpeedFan's got bugged, i'll re-open it", i do and it tells me the core is running at 114°. Inside of a second my PC turned off and i realised that although it was water cooled, the pump wasn't plugged in and as such it was cooking

Sorry for the long delays between replies, not always possible to get on my sisters laptop. Doing system restore and not updating windows seems to have fixed the lock up's but it was only temporary before so time to do what you have suggested, will reply later with the results.

Thanks again for all your help.

This sounds VERY similar to a problem I was having over the past month.

The PC would freeze, them sometimes BSOD or power off. This could be during boot, just after, or a few hours later.

At first I suspected malware...nothing, then messed up XP...reinstalled - Still happened.

I also could boot into safe mode without issue, and also into XP proper if I had no GFX drivers installed. This got me thinking it was the GFX card.

With the side off my case I listened for any noises (stuck fans etc), and found that the PSU was making a weird high pitched noise, most definately not from any of the fans.

Borrowed a pretty poor, but known working one from a mate and all crashes were gone. Ordered up a replacement and now have it fitted, still no crashes.

If the problem is related to Windows updates and a System Restore helps, switching them off for some days (to verify stability) should be considered. If the system is stable, a manual update should be performed, either configuring Updates NOT to install automatically (just download them) or doing it via web and installing them one by one, verifying the result after each update. These kind of operations shouldn't be hurried: write down every single update you apply every time and wait for the desired amount of time (at least some hours, in my opinion) to verify stability after having rebooted the PC. In this way you can track down problems to a single update and roll back in case something goes wrong. Then, when the update is identified, a search in the Microsoft Knowledge Base could help track down problems related to updates.

Quote from Albieg :

On the software side, you could have some nasty rootkitted software. I can't tell you how to look for rootkits since it's a job that requires some OS knowledge, but anyway if you look for some anti-rootkits you'll find them on the net.

I've used Blacklight rootkit scan before, its only a trial but it does the trick...fast and small(833kb),

Greboth start in safemode and run blacklight and if possible show us what processes XP is loading at startup by running msconfig and select the startup tab.run>msconfig

If the problem is software related(if you're lucky ) you'll have to check for any mal windows services that XP might be loading at startup causing conflicts.run>services.msc

Your friend might also be right about a bad driver being installed...but dodgy drivers can be time consuming to trace...so start with what XP loads 'processes and services' first.

Quote from CSU1 :

I've used Blacklight rootkit scan before, its only a trial but it does the trick...fast and small(833kb)

I don't use it. I believe with good reason that fast scans don't do everything needed to discover rootkits.

Quote from Albieg :

I don't use it. I believe with good reason that fast scans don't do everything needed to discover rootkits.

What other method\s would you use, or do you got a linkey for me?

Quote from CSU1 :

What other method\s would you use, or do you got a linkey for me?

The method varies, it depends on the complexity of the malware to identify/remove. When I approach an infected computer I don't make assumptions, so I check everything I can. A golden rule is: a bootcd doesn't load rootkits or malware, so an UBCD 4 Windows is extremely useful for some tools (for instance Rootkitty and Hijackthis PE).
The list of tools I sometimes or always use: an updated UBCD 4 Windows, Hijackthis (especially the PE version), Autoruns (much more often than the "normal" Hijackthis), Filemon, Regmon, Process Monitor, Process Explorer, The Avenger, GMER, Rootkit Revealer, IceSword, RKUnhooker, DarkSpy (rarely, it crashes often), SeDebugRestore. I always start with a manual removal and end with a general cleanup with antiviruses. Believe it or not, it is much faster than using several antiviruses/antispywares and then having to begin the job again from the start.
The list is partial, it could be much longer, but the combined use of those tools is more than enough in most cases.
www.antirootkit.com is a good starting point to know something more about rootkits.

Thanks for the info there Albieg...but im a bit stuck with this UBCD4win.

I completed the ubcd build(not with a windows disk but with my oem Toshiba Product Recovery cd) and have the iso ready, now i know that when the iso is burned to a cd i can pop into my machine and rescue my machine from any problems that might arise...but how is this different to my oem cd?...

Actually I started by making a 1 gig partition and putting the iso on that partition with the intention of using ubcd and the iso as a kind of system files replacement setup ie. the iso(F:\) would replace all my system files on c:\windows...is this possible or even practical?

Im guessing if the iso in F:\ where to replace all my important system files every time the possibility of anything important ever being changed is very small....but here i am stuck

Your OEM CD could be a simple Windows install CD that would give you limited diagnostic and repair resources (little more than recovery console), or a CD that does a complete reinstall of Windows and additional applications. It should in no way be meant as a complete diagnostic and repair tool. UBCD 4 Windows is NOT a reinstall tool: since it is meant as a system that can be updated and used at need, I see no good reason to install it as an additional partition.
Use it as an external resource when you need it. It can do a lot of stuff, from rootkit and malware scans to password and registry editing, to add users, to diagnose hardware, to fix file systems, to recover data, and much, much more. I can't tell how and when to use it, there are so many different uses that a description would be impractical here. There's too much to mention. A bit of logic and exploration will help you understand. It is meant as a tool for professional and power users, and in this possibilities are limited only by your knowledge and skill.

My brother's PC was suffering random lock-ups, freezes and reboots recently. sometimes was within a few minutes of booting up, sometimes it would run for a few days before doing it.
After trying everything else a new PSU was fitted....problem solved.


Not only does a 300w psu not sound enough these days, a cheap make 300w psu is asking for trouble.

Quote from The Moose :

My brother's PC was suffering random lock-ups, freezes and reboots recently. sometimes was within a few minutes of booting up, sometimes it would run for a few days before doing it.
After trying everything else a new PSU was fitted....problem solved.


Not only does a 300w psu not sound enough these days, a cheap make 300w psu is asking for trouble.

It has run for 18 months with no problem. I have tested it as much as my knowledge allows me and haven't found anything majorly wrong so it seems very likely it is the Microsoft windows update is the problem. Why it causes my machine to freeze I am at a loss

Edit: Also after testing no update fine, as soon I update and restart pc freezes.

Quote from Greboth :

Edit: Also after testing no update fine, as soon I update and restart pc freezes.

Just do updates manually one by one, write down the update number and test the system. Some updates are known to cause problems. You have to identify the one which is causing trouble and look for more information about it. MS Knowledge base may give you some clues.

Quote from Albieg :

Just do updates manually one by one, write down the update number and test the system. Some updates are known to cause problems. You have to identify the one which is causing trouble and look for more information about it. MS Knowledge base may give you some clues.

I know, my comment was more in response to it being the PSU.

Thanks for all the comments and helpful hints in sorting my PC out Kudos to you all.

Time to get cracking on the updates.