Ok, I'm trying to discern the underlying cause of the problem so it can be fixed.  It looks like your Windows installation got messed up, and there are hardware issues that can cause that, and there are software/security issues that can cause that.  It looks like you probably have some of each type of factor going on.
To try to cure the problem in the short term, you could try reinstalling your motherboard's chipset drivers and then your video drivers, and see if that helped.  Once you tell me what model of Soltek you have, I can provide links, so pop the cover and look for a model number on the motherboard, or look at your invoice.
If that doesn't help, the next thing would be a Repair-style reinstall of WindowsXP, which I can give a routine for doing that if the previous attempt doesn't work.
In terms of really fixing the likely causes for Windows getting messed up, I'd start by replacing that Xsonic 400W power supply with a known high-quality brand of power supply like Enermax, Fortron, or Antec, in the 400W+ range.  PSU quality is important, just like the octane of gasoline is important to some cars.  Also, chances are your memory could use a little more voltage than it's getting from the motherboard, simple to fix 
once I know what motherboard it is.
The security stuff could easily have something to do with it.  Whether it does or not, it would be a good idea to correct the lack of firewall, lack of Windows patching, and (?) lack of antivirus software.  You can fix all that in twenty minutes by installing WinXP Service Pack 2, and Grisoft AVG Free Edition antivirus or another antivirus of your choice.  Wormholes gone, Windows Firewall up, antivirus installed, Data Execution Prevention added.  

  More info 
here, make yourself spend 5 minutes reading it 

  If it saves your credit-card number getting picked off by a keystroke logger, it'll be worth it.
So I'll wait for info on what motherboard and what PQI RAM you've got.  Both of them should say right on them, or look at your invoice.