RAM Issues that nobody seems to find answers for

[Z40205]

I've done lots of Googling. I have two sticks of 168 pin sdram 1gb
each, exactly the same. Both sticks work in either slot. The bios
recognizes it as 2gb of ram. I'm having trouble getting both sticks to
post. One stick is 100% successful. I have to power off and on many
times to get it to post with both sticks in. Custom PC. It runs great
with two sticks. If I try and restart it with the two sticks I have
the no post problem again. All the fans come on and the HDD spins for
about 20 seconds and stops. Monitor is completely black. Never any
beeps from the bios. System and processor are running cool. If I can't
get it to work with the two sticks I will just use it with the one
stick. My MB don't laugh to hard is a PC Chips M930LR. It has been
good. Not many jumper options on the board that I know of other than
clearing the cmos which I have done. The manual is horrible and says
any jumpers you see on your board that you don't see in the manual are
for testing purposes only. I can't see or adjust RAM voltages in my
bios the way it is. Is this possibly a configuration problem I am
having or something else? Some people suggest a PSU problem but I
don't think it has a problem. It's 400W I have a Intel Pent4 2.6
processor. This does the job for me and fast enough as I'm not a
gamer. It brings Photoshop up fast with 1gb of ram.
Any tricks I can try? Thanks

 

[Grinder]

Wow, guy, paragraphs please.

I've done lots of Googling. I have two sticks of 168 pin sdram 1gb
each, exactly the same. Both sticks work in either slot. The bios
recognizes it as 2gb of ram. I'm having trouble getting both sticks to
post. One stick is 100% successful. I have to power off and on many
times to get it to post with both sticks in.

Custom PC. It runs great
with two sticks. If I try and restart it with the two sticks I have
the no post problem again. All the fans come on and the HDD spins for
about 20 seconds and stops. Monitor is completely black. Never any
beeps from the bios. System and processor are running cool. If I can't
get it to work with the two sticks I will just use it with the one
stick.

I had a very similar problem with RIMMs in an Intel board. From a
"cold" start, the machine would start up just fine. Restarting, though,
would always fail. I do not believe that it was heat related as I could
generate the effect with the machine gutted on a table with box fans
blowing right on it. Finally I bit the bullet and bought another pair
of RIMMs and the problem went away.

My MB don't laugh to hard is a PC Chips M930LR. It has been
good.

Yeah, except for the not POSTing part. <g>

I've got an M920LR and it is very fickle. It took me awhile to find
memory it was happy with. There was no pattern to what was acceptable,
and what was not. Sorry I can't give you a better answer.

The board sort of fell into my lap so I can avoid being hypocritical by
saying: Don't ever buy a PCChips (PCChimps) board. Before I ever got
the M920LR I knew they had a bad reputation, but the frustration I've
endured since has made be a believer.

Not many jumper options on the board that I know of other than
clearing the cmos which I have done. The manual is horrible and says
any jumpers you see on your board that you don't see in the manual are
for testing purposes only. I can't see or adjust RAM voltages in my
bios the way it is. Is this possibly a configuration problem I am
having or something else?

My M920LR has a RAM voltage jumper, as well as a whole line of jumpers
for selecting between DDR and "DIMM" memory, which presumably is DDR vs.
SDR. Those jumpers were mentioned in my manual, which appears to only
be marginally better than what you have for the M930.

Any reasonably designed board should be able to sense which set of slots
are populated and adjust accordingly, but we are talking about PC Chips
here.

Some people suggest a PSU problem but I
don't think it has a problem. It's 400W I have a Intel Pent4 2.6
processor. This does the job for me and fast enough as I'm not a
gamer. It brings Photoshop up fast with 1gb of ram.

The power supply is always suspect. The rating on the label is not part
of the electrical composition of the supply, neither at the time it's
new, nor when it's older and failing.

It's good general advice, but you can reduce the load by stripping your
system down to its minimum state. If your PC will fire up every time
with two modules and just a hard drive (no optical drive, floppies,
add-in cards, etc.) then I might wonder more about the power supply.
(If you can eliminate your problem by going to a minimum state, just
start adding bits back in until the problem reappears.)

Any tricks I can try? Thanks

I like the severed thumb bit, but have had to ply it upon random kids in
the supermarket since my nieces and nephews have made it to junior high.

And, no, that's not me in the video.

 

[Paul]

I've done lots of Googling. I have two sticks of 168 pin sdram 1gb
each, exactly the same. Both sticks work in either slot. The bios
recognizes it as 2gb of ram. I'm having trouble getting both sticks to
post. One stick is 100% successful. I have to power off and on many
times to get it to post with both sticks in. Custom PC. It runs great
with two sticks. If I try and restart it with the two sticks I have
the no post problem again. All the fans come on and the HDD spins for
about 20 seconds and stops. Monitor is completely black. Never any
beeps from the bios. System and processor are running cool. If I can't
get it to work with the two sticks I will just use it with the one
stick. My MB don't laugh to hard is a PC Chips M930LR. It has been
good. Not many jumper options on the board that I know of other than
clearing the cmos which I have done. The manual is horrible and says
any jumpers you see on your board that you don't see in the manual are
for testing purposes only. I can't see or adjust RAM voltages in my
bios the way it is. Is this possibly a configuration problem I am
having or something else? Some people suggest a PSU problem but I
don't think it has a problem. It's 400W I have a Intel Pent4 2.6
processor. This does the job for me and fast enough as I'm not a
gamer. It brings Photoshop up fast with 1gb of ram.
Any tricks I can try? Thanks

The motherboard uses SIS645/961 Northbridge/Southbridge. The SIS645
Northbridge is the one that interfaces to the RAM.

The largest SDRAM I have here, is in the form of 512MB sticks. The
largest DDR is 1GB. So my first question is whether it is SDRAM or
not. I did find one example here, of a PC133 1GB stick, so I guess
they do exist. This one is pretty ordinary looking, no tricks.
Uses (16) 64Mx8 chips. They probably weren't making these in 2001/2002.

http://www.valueram.com/datasheets/KVR133X64C3_1G.pdf

The PCchips manual for the board, is on the ECS site now. It is
an MSWord document. The board must be auto switching the voltage
to the SDRAM or DDR, based on what it detects by scanning the
SPD EEPROM. (Some dual RAM type boards used to use a jumper for
that, but those boards probably killed more RAM than they worked
with.)

http://download.ecsusa.com/dlfilepcc/manual/m930/930s15.zip

You could have a look in CPUZ (a windows program), and see how
the actual memory running conditions, compare to the values
stored in the SPD. Maybe you'll notice too aggressive a
setting in there.

http://www.cpuid.com/cpuz.php

Paul

 

[Paul]

That seems awefully fancy for something from PCChips, I'd
imagine it's supplying both voltages to each respective pair
of memory slots at all times.

I expect you have to make a choice as to what voltage to apply
to VIO on the Northbridge. The Northbridge interface should
run from the same voltage as the VIO on the memory. You could
leave 3.3V on the SDRAM slot, 2.5V on the DDR, but make a
decision as to what to apply to the Northbridge VIO.

I have a board here, that has both SDRAM and DDR, and they used
what look like QuickSwitches between the two pairs of slots.
(They hid them, by putting an Asus brand name on the chips.)
As transmission gates, that clips the signal level, and allows
mixing two voltages. But you need a bit of spacing between the
RAM slots, to put down the (ten) tiny chips. That sounds a bit
too fancy for PCChips. I don't see enough room between the two
pairs, for that here.

This might be the M930LR here.

http://www.clubedohardware.com.br/imageview.php?image=6350

This is the TUA266 for comparison, with chips between the
two sets of RAM.

http://www.multi-hardware.com/bdd/imgnews/TUA266.jpg

What is also amazing about the M930, is that the benchmark
results are so close for the two memory types.

http://www.clubedohardware.com.br/artigos/639/5

Paul

 

[Paul]

Once you get it posting with two memory modules, run
memtest86+ for several hours.

I suspect it's posting with one memory speed, a speed that
is instable, then appling the bios settings for the bus
speed. If it crashes before it runs long enough to apply
the new bus speed, it can't continue. Basically the only
resolution for this would be a bios update or different
memory with higher spec'd speed capability, "IF" that is the
problem. I would as soon get a different motherboard
instead since it's a PCChips.

My Asus P4B board has S478 and uses SDRAM. The manual says
it'll take 3x1GB, but the most I've used is 3x512MB. I
think it is limited to FSB400, like the SIS645.

Paul

 

[larry moe 'n curly]

The motherboard uses SIS645/961 Northbridge/Southbridge. The SIS645
Northbridge is the one that interfaces to the RAM.

The largest SDRAM I have here, is in the form of 512MB sticks. The
largest DDR is 1GB. So my first question is whether it is SDRAM or
not. I did find one example here, of a PC133 1GB stick, so I guess
they do exist. This one is pretty ordinary looking, no tricks.
Uses (16) 64Mx8 chips. They probably weren't making these in 2001/2002.

http://www.valueram.com/datasheets/KVR133X64C3_1G.pdf

The PCchips manual for the board, is on the ECS site now. It is
an MSWord document. The board must be auto switching the voltage
to the SDRAM or DDR, based on what it detects by scanning the
SPD EEPROM. (Some dual RAM type boards used to use a jumper for
that, but those boards probably killed more RAM than they worked
with.)

Are you using DDR SDRAM and SDR SDRAM modules simultaneously? I don't
think that's allowed because I have an ECS P4S5A mobo, which is also
based on the SiS 645 chipset, and it runs all the memory sockets at
the same voltage, either +3.3V (for SDR) or +2.5 (DDR). OTOH I've had
problems using Kingston 256MB PC2100 and 512MB PC3200 DDR ValueRAM
modules with this mobo, more so than with an ECS brand SiS 735 mobo.
Kingston RAM modules have been unreliable for me, and this varied by
production run and not just randomly. Most of the bad ones worked
fine after I slowed the bus speed or other timings to below specs.

 

[larry moe 'n curly]

Are you using DDR SDRAM and SDR SDRAM modules simultaneously? I don't
think that's allowed because I have an ECS P4S5A mobo, which is also
based on the SiS 645 chipset, and it runs all the memory sockets at
the same voltage, either +3.3V (for SDR) or +2.5 (DDR).

CORRECTION: What the heck was I thinking? Of course the SDR slots
are run at +3.3V and the DDR slots at +2.5V. What I should have said
was, the higher voltage of the SDR's data output lines could damage
the DDR modules because those lines are connected together.