I had the same problem with a Presario 4540 when I replaced my 16 MB chip
with a 32 MB chip 7 or 8 years ago. The base problem is that the
motherboard requires memory modules with SPD - Serial Presence Detect. The
idea behind SPD is that the memory stick had an extra EPROM chip on the
stick that was able to identify itself with the mobo. When the power was
turned on, the motherboard received information about the memory stick type
by reading the information from this EPROM.

At the time I thought it was a very forward-thinking idea from Compaq. At
least, that's what I thought until I tried several different 32 MB chips and
none of them worked because the more standard memory sticks didn't have
these little fancy self-identifying EPROMs. If there was a way to disable
this using the BIOS or a jumper setting, nobody knew it at the time. I
ended up purchasing memory directly from Compaq because that's the only
place which sold chips which contained SPD. The cost was not cheap - it was
about 4-5 times higher than other 32 MB chips at the time.

And as someone has already pointed out in this thread, that model has 16 MB
of build-in memory and only a single DIMM expansion slot taking a max of 32
MB. So even if you purchase a 32 MB chip to replace your 16 MB chip, you're
going to max out at 48 MB and have a 16 MB loose keychain left over.

That was such a racket. I look for those types of things now when I
purchase systems.

-Jack

"Michael Abraham" wrote in message
rs.com...
I have tried a number of memory sticks in my Presario 4540 and the only
one
that works is the original Compaq memory supplied with it. But who can
live
with 32mb? Help! Does only Compaq memory work in this thing?
Thanks

--
Michael Abraham
Toronto, Ontario
Canada
(416) 654-2272