Hi PCBuilders,

I have a P166MMX system with a clone 430TX mobo, AMI BIOS,
3.2GB Quantum Fireball SE with UDMA and a Virge DX graphics
card, running Win95 OSR2 and FAT32. The system shipped with
16 MB FPM SIMMs.

One month ago I installed two 32MB SDRAM DIMMs and got rid of
the older SIMMs. The system booted up, memory tests ok and
everything was fine, but since then I experience random lockups
and/or resets or random weird MS blue screens referring to
invalid page address.

Now I think the memory upgrade is the most likely offender :)
But I am baffled by memory and system tests which report no
memory error: I also tried DOS 6.22 HIMEM.SYS which reported
no problem.
I can have DIMM replaced if they prove defective, but how is
possible memory fails without affecting sys tests ? It is
possible to test system memory in a more thorough way than
BIOS does without resorting to hardware probes ?

Other possible offenders could be:
- BIOS settings ? I did not change anything in BIOS after upgrade,
  leaving memory options on Auto.
- DIMM voltage ? Mobo has a jumper referring to memory voltage
  rating which, according to mobo doc, should be set to 3.3V
  for SDRAM, I checked and it was already set on 3.3 V, so i left
  it unchanged.
- Grounding ? I had to dismantle the mobo to gain access to DIMM
  slots (talk about cheap PC clones) and maybe I got something
  wrong in reassembling it.

I'd like to know if someone else experienced similar problems
after a RAM upgrade, and if there exists a utlility which really
tests all systems memory.

Thank you in advance for your help

*******************************************************
Gianluca Zanetti         Breda Costruzione Ferroviarie
[log in to unmask]      Via Ciliegiole 110b
tel +39 573 370581       51100 Pistoia (PT)
fax +39 573 370292       Italia
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