Random Lock-Ups AMD XP 1800+

I experience random lock-ups with my self-built computer. Everything is just frozen and I have to press the reboot button.

Sometimes when my computer feezes and I restart using the reboot button I automatically get to the BIOS when starting up again. In the BIOS the CPU speed has automatically changed! It's set 1150 Mhz instead of 1533 Mhz and System / PCI Frequency has also automatically changed from 133 / 33 to 100 / 33. I just change it back and leave BIOS but I always have a somewhat strange feeling .... I don't think this is supposed to be like that.

My computers specifications:

AMD XP 1800+
Kingston 512 MB DDR RAM
Asus A7V-266E Mainboard (with newest BIOS 1009)
I have also installed latest VIA4in1 drivers v4.40
Asus GeForce 3 Ti 500 (with newest Detonater drivers)
Soundblaster Audigy w/1395
IBM Deskstar 60GXP HDD
Asus CD-S520 CD-ROM
Plextor 24/10/40 CD-Writer
Windows ME with all updates

I don't think it's a heat problems. CPU temperature is usually between 50 and 60 degree celsius.
Motherboard temperature is usually between 35 and 40 degree celsius and HDD temperature is between 30 and 40 degree celsius.

I have run memtest-86 v3.0 to check my memory. Altough it took a very long time (9 hours) to complete all tests there were no errors. Especially test 11 took a very long time to complete. Im not sure if that's normal.

I have also formated my c drive and installed Windows ME again.

I have a 300W power supply. Here are some figures from motherboard monitor:

+3.3 3.07 - 3.12V Average 3.11V
+5.0 4.78 - 4.89V Average 4.87V
+12.0 12.40 - 12.65V Average 12.52V
-12.0 (-14.80) - (-12.07) Average -13.49V

Vcore of my CPU is set to 1.75V in BIOS and motherboard monitor reports a Vcore of 1.85V. Is that normal?

Thanks in advance for any help!

Scipio

Just a tad?

"When there's a will, there's a way."

Thanks for your help.

I will order a 400W PSU tomorrow. I hope it will fix my problem

BTW ..... how high should my voltage be?

Cheers

Scipio

heh mine drop to below 4.64V on my 5V line...but the 430W Enermax is already shipping to me as we speak, i've suffered random lock ups too long

<font color=red>isit alan?</font color=red>