Archived from groups: alt.sys.pc-clone.compaq (
More info?)
Most SyncDRAM DIMMs today support SPD. The issue with the 4500s was a timing
issue. PC66 (10-12ns) DIMMs were required. Very few PC100 (8ns) DIMMs would
work. Kinda hinky, I know, but true nonetheless.
HH
"Jack Cooper" <jackNOSPAMcooper@comNOSPAMcast.net> wrote in message
news:TIidndQgM-e2yJXcRVn-gg@comcast.com...
> 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" <bb.parris@rogers.com> wrote in message
> news:yPDKc.22$wyV.3@news04.bloor.is.net.cable.rogers.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
> >
> >
>
>