Optimal Motherboard Settings KV8-MAX3 - Memory Problems

Ok, so first of all my setup :)

Athlon64 3200+ Skt 754
Abit KV8-MAX3
2 x 512 MB Twinmos Dual Matched Sticks PC3200 Cas 2.5

Right, I've had the system like nearly 2 years or something, and I recently noticed on boot after the memory check, it reports the memory clock speed as DDR333..
Now the board is supposed to be DDR400, and I have DDR400 memory in there, so my question is, why isn't it running at full speed?!

Now, I have recently been playing with the OCguru jobby and I have the FSB set at 211 (it was higher like 220 and ran ok only a few degrees hotter but I'm not sure if this is whats caused the memory problem)

I have also been in the bios and tried setting this manually. Currently memory speed is set to AUTO and thats setting it to 166 DDR333. I have selected the option SPD(??) and set 200 DDR400. Now the system boots fine, and reports DDR400 after the memory check. Soon as it booted I started to play a movie (x264 HD encode) and shortly later, I had the first BSOD (blue screen of death) I have seen for as long as my poor warped little brain has seen in a long time.
Naturally I assumed that this was due to me setting the DDR400 thing in the bios, so I went back and changed the setting back to AUTO just to be safe and havent touched it since.. Its now gone back to DDR333.

So, can anyone enlighten me? Is this something I am doing wrong??

Cheers!
Fink.

Place the memory in either 1 & 2 or 1 & 3, Go into the BIOS and set memory by speed. You will also have increase the voltages to make the system stable.