Random Lock-ups (In and out of HL2)

[FaultySanity]

System specs (my computer is only a few weeks old)

-2.4 Ghz AMD64 Athlon CPU
-Abit KV8 Pro
-1GB PDP PC3200 RAM
-480w PSU
-80GB HD 7200rpm
-PNY Geforce FX 5200 ultra (128MB, 128Bit)

This is the usual scenario:

I load-up steam, and enter go in CSS (or HL2, ill use CSS for example). In case it matters, i have a few prompts that i popped in the shortcut. It reads as follows:

"D:\Program Files\Steam\Steam.exe" -applaunch 240 -heapsize 384000 -zone 16000 +mat_forcehardwaresync 0 +snd_async_prefetch_priority 1

I have tried with both Shortcut and trough Games in steam.

So anyway, I pick a server, and go into it. I get into the server, and generally within the following 1-3 minutes i will lock-up. The acual crash is rather strange. Its as if it repeats 2 out of 6 seconds of a sound, then everyone 20 seconds or so, it will add a second to it.

i.e ('e' represents a length of a sound)

*locks up*
e - e - e - e
*10-20 seconds later:
ee - ee - ee- ee
*10-20 seconds later
eee - eee - eee - eee

And by then i usaually reset. My keyboard doesnt respond (caps lock light doesnt turn on when locks up) nor does Ctrl + Alt + Del work.

So if anyone can tell me how to fix this problem with locking-up, Thank you in advance

:thumbs: