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Old May 13th 05, 05:35 AM
BigJim
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no really the p2b needs low density ram
"P2B" wrote in message
. ..
Anyone know what causes erratic RAM detection on P2B series motherboards,
particularly at 133Mhz FSB?

I've never had any problems running 768MB (3x256MB) on my P2B-DS boards,
and one is fully loaded with a gig.

I recently purchased a bunch of used 256MB sticks, mostly Micron but a few
are other brands, with the intent of upgrading our single processor P2B
systems from 256 to 512 or 768MB.

I tested it all in matched pairs on a modified P2B-AE running a P3-S
1.4Ghz CPU (133Mhz FSB) - configured the BIOS for 222 timings regardless
of SPD, and ran memtest86 3.0 in all tests mode for at least 5 full passes
on each pair.

All testing completed without a single problem or error, but when I
install in the target systems I encounter nothing but grief :-(

On one P2B-AE system, the BIOS only detects either 64MB or 128MB from cold
start when 512MB is installed, and it won't POST on reset - has to be
powered off to try again. I tried all the tested pairs, and also mixed
brands, but couldn't get it to detect more than 128MB when both RAM slots
were filled - not even at 100Mhz FSB and 333 timings - but this one has
the same board revision and BIOS as the test system that detected 512MB
every time!

Similar story on a P2B-S machine, although I eventually found a
mixed-brand pair that works properly in this system - but no way will it
detect three sticks.

RAM voltage on all systems is within 100mV of 3.4V, the only significant
difference is Tualeron processors in the target systems vs. a P3-S in the
test system - but that seems unlikely to affect RAM detection.

All very mysterious and annoying - comments or suggestions appreciated.

P2B