PC-133 Memory

  • Thread starter Thread starter Daniel Mandic
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Daniel Mandic

Which brand SDRAM, is the best choice today, for expanding the ASUS P2B-F
Mainboard to 1024MB (4 times 256MB DIMMs)?
16Mx8, of course.

I would need stability reserves up to 133MHz 2220 timing. Cl.2!


I am also interested in exotic brands with more MHz, PC150 or such kind.
Mushkin, etc..
which work very well with the i440BX.





Kind Regards,

Daniel Mandic
 
Daniel Mandic said:
Which brand SDRAM, is the best choice today, for expanding the ASUS P2B-F
Mainboard to 1024MB (4 times 256MB DIMMs)?
16Mx8, of course.

I would need stability reserves up to 133MHz 2220 timing. Cl.2!

I am also interested in exotic brands with more MHz, PC150 or such kind.
Mushkin, etc..
which work very well with the i440BX.

Kind Regards,

Daniel Mandic
Click to expand...

Go to http://www.crucial.com/ and enter your motherboard name in
the search box. There is some PC133 CAS2 memory available. There
is also some PC100, so be careful which one you select.

If your OS is Win98, be aware that 512MB is the limit for perfect
stability. Between 512MB and 1024MB requires editting an .ini file.
On my P2B-S, I couldn't even get 768MB to work properly, even
though I tried the standard fix. It does work for some people,
but it just didn't work well for me. I ended up with 2x256MB
Crucial memory on that system as the final configuration. You
shouldn't have a problem with more modern OSes.

( Search terms: MinFileCache MaxFileCache Vcache SYSTEM.INI )

Here is an example mentioning the issue, without giving an
exact recipe on how to edit the file:
http://support.microsoft.com/kb/253912/EN-US/

So-called performance memory (PC150, PC166) has pretty well
disappeared. The user who posts with the nickname "P2B" is the
guy to ask about stuff like that. His email address is at the
bottom of this web page: http://www.tipperlinne.com/p2bmod and
he may be able to identify a source of such memory. He
repairs and custom mods 440BX based motherboards.

One thing to remember, is as the speed goes up, the maximum number
of sticks of RAM you can use goes down. Four sticks run at PC100,
three sticks at PC133, and I'm not going to guess about PC150 or
PC166. If you do want to have 1GB of memory, be prepared to slow
down the FSB if it isn't stable (it might or might not work -
test with memtest86+ from memtest.com). Since a P2B-S can only
run at a maximum of 112Mhz, this is not a problem for me.

Paul
 
That chipset will have troubles with out of spec timings. The
chipset itself will only support pc100, but it does run pc133. The
problem begins when you run the memory higher than that, it just
doesn't seem to count properly and your benchmark scores will decline.
I have the PB3-F with good micron and infineon cl-2-2-2 pc-133.
When I set the bios at auto spd, it could not register the dimms rated
timmings properly so I set them manually just to run at pc133 and the
rated cl settings. Although that did work, I could not overclock my
133-cpu without having that negative effect on the memory. The chipset
cannot do it, even if the cpu and memory can...!
 
Daniel said:
Which brand SDRAM, is the best choice today, for expanding the ASUS P2B-F
Mainboard to 1024MB (4 times 256MB DIMMs)?
16Mx8, of course.
Click to expand...

As Paul said, Micron is an excellent choice, and you get guaranteed
compatibility if you buy it from www.crucial.com - but...
I would need stability reserves up to 133MHz 2220 timing. Cl.2!
Click to expand...

I recently upgraded RAM in several of my P2B-S and P2B-DS systems using
whatever 256MB PC133 sticks I could find locally, provided they were
16Mx8 and cheap - which ended up including Micron, Corsair (Micron
chips), Infineon, Hynix, and AmZor brands. Most of them were rated PC133
CL3, but all passed overnight memtest86 testing at CL2 timings (143Mhz
BIOS setting) on a P2B-S running 133Mhz FSB. IME very few PC133 sticks
fail memtest at 133 CL2 but pass at 133 CL3 on P2B series mainboards, so
I don't specifically seek out CL2 rated chips.

1GB RAM at 133Mhz FSB is possible on P2B series mainboards, but many
refuse to recognise all the installed RAM at boot. Boards which do
acknowledge 1GB usually only do so with the help of a "BIOS Trick" - you
power up the board, it POSTs and counts an apparently random amount of
memory, you hit DEL to enter the BIOS, then ESC and Y to exit without
saving. The board resets and counts all RAM correctly. I don't know why
this works, but IME if it works once on a given board and RAM
combination it will work consistently in future. I set the BIOS to halt
on a hardware error (usually Tualatin Vcore too low) as a reminder to
enter/exit BIOS before booting the OS.

I've never had 1GB at 133 work using matched sticks - my primary P2B-DS
system runs Micron, Infineon, Micron, SimpleTech in that order. They
won't work in any other order, nor will 4 x Micron work.

Swapping RAM in, out, and between slots until you find a combination
that works appears to be the only viable approach. I recommend clearing
CMOS before you start, and testing RAM detection using BIOS defaults -
otherwise inconsistent results are likely. Wait until you find a
combination that detects correctly before adjusting RAM timings and
running memtest.

Another consideration is RAM voltage, although this is usually only a
problem on P2B-DS boards. Vio needs to be at least 3.4v (preferably
measured with a DMM) for maximum RAM capacity.

Of course you can avoid all of the above by lowering FSB - IME almost
all P2B series boards will run 1GB at 124Mhz, the problems start at 133Mhz.
I am also interested in exotic brands with more MHz, PC150 or such kind.
Mushkin, etc..
which work very well with the i440BX.
Click to expand...

I have a couple of P2B-S systems running at 150Mhz FSB and CL2 timings
using Corsair XMS150C2 RAM. One consistently detects 512MB (2x256) on
power up, the other one refuses to even POST at 150 if more than one
stick is installed. 768MB won't work on either board. Others have
reported similar results using Kingmax TinyBGA PC150.

HTH

P2B

http://tipperlinne.com/p2bmod
 
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