P2B-F memory sizes

[Rajiv Niles]

Hi everyone,

When I plug in a Kingston 256MB DIMM into my P2B-F, the BIOS picks it up
erratically. Sometimes, it picks it up as 128MB and other times it picks it
up as 256MB. The motherboard manual says it does support 256MB PC100.
However, I am clocking at 133MHz as the processor requires it.

Is there any way to fix this ? Anyone else had the same experience ?

Rgds,
Rajiv.

 

[Bob Knowlden]

Is the DIMM low density?

I believe that all 440BX boards (like the P2B-F) require low density RAM. I
don't know if it's an absolute, but the low density 256 MB DIMMs I've seen
have used sixteen RAM chips. (18 chips for ECC.)

I had a similar problem with a different 440BX board, a Soyo 6BA+IV. I got
two 256 MB DIMMs from www.crucial.com, and they worked well with a 7.5X133
(1 GHz) PIII.

HTH.

Bob Knowlden


Address may be scrambled. Replace nkbob with bobkn.

 

[Rajiv Niles]

Bob, you're absolutely correct. I tried a low density DIMM and it worked.

 

[timmy]

I have had the same experiance with the pb3-f when overclocling. This
was using crucial or infineon 256mb modules, non-ecc.

I believe it is a chipset limitation. I have tested various scenario's
and it always results the same when at 133mhz bus speed. You could try
running the memory at "auto" when the bus is at 133mhz. The memory
will clock down and it may count correctly...but I think you'll find
that running a 100mhz cpu with your ram speed higher (ie: 2-2-2) will
result in a more stable enviroment.