Old Memory Question

This isn't exactly the right section for this.Sorry
A friend of mine has an old pc with a Pentium 100MHz and 16mb of RAM in it (that's all i've been able to get out of her!).She has been complaining of it being slower than usual so i was thinking i would have a look in all the old bits of memory i have lying around at home to see if i can find any to put in there for her to see if it makes a difference.
The main problem for me is that my knowledge of memory types is not good for the pre- PC100 days.Can you tell me what type of RAM her computer is likely to have?How can i tell what type of memory the stuff i have is?I am a student and all the old memory i have is at home so i am just getting my dad to send it up to me so i won't be able to see what motherboards it has come from etc.
Any help would be much appreciated.

no matter how hard you try, you can't polish a turd. :]

It most likely uses EDO or FPM modules. FPM is also called "Fast Page Mode" or Non-Parity. Most people don't know that these two types can be mixed of you put the FPM mode in the first slots. So my suggestion is that, unless you find SDRAM DIMMs in there (highly unlikely), buy some EDO and put it in the 2nd and 3rd positions.

The type of EDO and FPM I'm speaking of are 72-pin SIMMs, they are 32-bit so they need to be paired for the Pentium CPU.

<A HREF="http://www.computersurplusoutlet.com" target="_new">http://www.computersurplusoutlet.com</A> is a good place to find replacement SIMMs.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

I reckon the 486 will almost certainly have EDO stuff in, the Pentium 75 will also probably. IIRC, back in those days the RAM speed was always given as the access time (i.e. NOT 100Mhz, 133Mhz, etc, but 6ns[nanoseconds], or 7ns), but I can't remember whether those old mobos would default to the slowest RAM in there, or needed manually configuring, or simply wouldn't work with mis-matched RAM... Good ol' Crashman can probably shed some light here.

The PII 400 will probably have SDRAM though.

I don't know if you've ever bothered looking at the old 72-pin stuff, but if you know what SDRAM looks like (which I assume you do) you'll have no trouble with 'em. The slots usually worked by sticking the ram into the slot at a shallow angle, and tilting it upright until it snaps into place.

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<font color=red>The preceding text is assembled from information stored in an unreliable organic storage medium. As such it may be innacurate, incomplete, or completely wrong</font color=red>

The Pentium 75 should have EDO or FPM non-parity. Either should work with your friend's computer. If it's a mix of EDO and FPM, you might have to change the order it's mounted in so the system addresses the slower FPM first.

The 486 could come with a variety of memory, from the old 32-pin SIMMs found in XT's, to 72-pin Parity or Non-Parity. At any rate, if you use up the RAM from the P75 you probably won't need any from the other systems.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

Many thanks everyone .I'll update this thread in a couple of days when all those old memory sticks have arrived and enlist your help in classifying them.Unfortunately i won't know which system they have come from because i am just getting them posted to me all together.I'll also try to get over to my friend's house to see if i can get a look at her mobo.

no matter how hard you try, you can't polish a turd. :]

Ah true, but you can still mix EDO and FPM in most systems if you put the FPM in the first bank.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

I am appalled!The thought hadn't crossed my mind!<pre>...for more than a few hours!</pre><p>

no matter how hard you try, you can't polish a turd. :]