PC wont read RAM.

[greg77 via HWKB.com]

I have an old P3 500mhz compaq deskpro PC I got (2) 256MB RAM sticks for it
and for some reason the PC wont except the sticks, it makes a series of beeps
when I turn the power on and then just doesn't boot up, they are the same as
the original sticks as far as being PC133 168pin DIMM except they are 256
instead of 64 and 128. I recently put in two 128 sticks and they went in fine.
I'm not to savvy about the inner working of a PC and how things interface
with each other, Physically I know where things are and how they go together.
I wondered if maybe because it's an old PC that it just doesn't read the 256
sticks because they are new. The 128 sticks I put in were out other systems.
Thats my theory anyways.
I was hoping someone could shed some light on the problem.
Thanks for your replys. GREG

 

[GIRunit]

check to see if they r in there tight. i cleaned my comp the other day
and one of my ram cards came a lil bit loose and it did the same
thing.

 

[kony]

I have an old P3 500mhz compaq deskpro PC I got (2) 256MB RAM sticks for it
and for some reason the PC wont except the sticks, it makes a series of beeps
when I turn the power on and then just doesn't boot up, they are the same as
the original sticks as far as being PC133 168pin DIMM except they are 256
instead of 64 and 128. I recently put in two 128 sticks and they went in fine.
I'm not to savvy about the inner working of a PC and how things interface
with each other, Physically I know where things are and how they go together.
I wondered if maybe because it's an old PC that it just doesn't read the 256
sticks because they are new. The 128 sticks I put in were out other systems.
Thats my theory anyways.
I was hoping someone could shed some light on the problem.
Thanks for your replys. GREG

Most commonly this is due to using high density PC13 memory
in a motherboard that needs lower density PC100 instead.

Try installing only one module in each/both slots.

 

[Mike Walsh]

If the 256 MB DIMMs have 4 chips they might be too high density to work. Try a DIMM with 8 (lower density) chips.

 

[Paul]

I have an old P3 500mhz compaq deskpro PC I got (2) 256MB RAM sticks for it
and for some reason the PC wont except the sticks, it makes a series of beeps
when I turn the power on and then just doesn't boot up, they are the same as
the original sticks as far as being PC133 168pin DIMM except they are 256
instead of 64 and 128. I recently put in two 128 sticks and they went in fine.
I'm not to savvy about the inner working of a PC and how things interface
with each other, Physically I know where things are and how they go together.
I wondered if maybe because it's an old PC that it just doesn't read the 256
sticks because they are new. The 128 sticks I put in were out other systems.
Thats my theory anyways.
I was hoping someone could shed some light on the problem.
Thanks for your replys. GREG

High density versus low density RAM, refers to the number of address bits
used on the RAM chips. You need fewer high density chips to make a DIMM,
than low density chips. Thus, if you have a 256MB DIMM with 8 chips, that
is high density. A 256MB DIMM with 16 chips is a low density DIMM. For
chipsets like 440BX from that era, the low density DIMM with 16 chips is
more likely to work.

If you go to Crucial.com and find your computer in their lists, they
will make sure you get the right RAM. There are other companies
as well, like Kingston, that maintain lists of the right RAM for
a computer. If you use one of those lists, you stand a better
chance of getting the correct RAM.

I use a couple Crucial 256MB 16 chip DIMMs, in my old 440BX based board,
and they work well.

Paul

 

[kony]

If the 256 MB DIMMs have 4 chips they might be too high density to work. Try a DIMM with 8 (lower density) chips.

The typical low density memory I'm thinking of would have 16
chips per 256MB.