Why are SDRAM DIMMS detected by old mobos as 1/4 its real ca

[HamsterX]

Why are SDRAM DIMMS detected by old mobos as 1/4 its real size ?...

That's it... that old Soltek SL-53D5 mobo in now working great with it's new AMD K6-2 @ 450 MHZ. Now it only needs plenty of RAM. Only 4 SIMM and 1 DIMM slot available. Trashing old SIMMs and trying 128 and 256 MB DIMMs... they are detected as having 32 and 64 MB capacity...

Help.... anyone ?

HamsterX

[BearCat]

This Apollo VPX motherboard supports 72-pin SIMMs and
168pin DIMMs (3.3V unbuffered type)
of 4MB, 8MB, 16MB,or 32MB to form a memory size between 4MB to 512MB
(total of 6 rows are supported).

Might be a problem with "big" DIMM's ?
Are you using the latest BIOS ?

BC

[HamsterX]

Yes, BIOS is the latest one. VPX-B.

From what I see, the mobo supports 4 SIMMs and only 1 DIMM... that is five memory slots.

If the max DRAM socket size is 32 MB, then 5x32 MB = 160 MB.

How can it support max 512 MB avoiding "big" memory modules ? Or am I doing any mistake ?...

HamsterX

PS: And this behavior is not new... I saw this also with a Soyo 430VX mobo... 4 SIMM + 1 DIMM and 128 MB detected as 32 MB...

[Crowdirt]

Hi Folks, not sure if any of you remember the Intel RAMBus gaffle, but one could say that almost all MOBOs have problems with Memory Slots to some extent. Some MOBOs do not implement enough Address Lines to support the "Largest" capacity Panels that will physically fit in the slots. Others have Timing/Signal Loading problems so the maximum number of panels do not work properly. Some MOBOs will only work with certain "Brands" of Memory Panels. A mixture of different Panels can cause various problems, mostly timing related also. Even if it seems to work ok, there can be some intermittent problems and Crashes occurring if you do not have everything Just Right.

[HamsterX]

Probably you're right...

I'm planning to spit some WD40 in that mobo and see if the memory slots behave

Thanks Crowdirt.