WHO IS THE CULPRIT - RAM OR MOTHERBOARD ?

Am using P4 2.8 HT with 2 x 256 mb DDR SDRam 400 and Intel DGBF D865GBF motherboard.
On running WINDIAG (Memory Checking software) it reports :

LRAND, STRIDE6, STRIDE38,WSTRIDE
AND ERAND failed.

However when I check each module individually everythining is ok.

I presume that both my RAM modules are OK and that something is wrong with the motherboard.

Can someone of you fellows help me ?

Nariman