konc wrote:

jheronimus wrote:

Murugan wrote:

Also, I might be wrong, but almost all 32MB SDRAM sticks are PC-100 or PC-133, so you can't really go wrong there.

Actually most of 32MB SDRAM sticks were rated @66MHz. I'll refrain from stating that 133MHz 32MB modules don't even exist in case I'm totally wrong with this, but I was working in the field at that time and they were certainly not common.

I'm pretty sure they exist and they are definitely not common, most were PC-66 with 16 chips (2 each side).

Most PC-100 ones (and faster) had like 4 chips on the DIMM, either 2 on each side or all 4 on a single side (and usually turned around 90 degrees compared to the PC-66 DIMMs)

edit: I started doubting if I was correct about the PC-133 32MB modules, so I've been diving into boxes of memory modules and online spec sheets.

I do not have a PC-133 marked 32MB module, but at best have a couple 32MB PC-100 cl2 modules.

4 chips on 1 side (other side empty), DIMM sticker: MT4LSDT464AG-10EB2 PC-100-222-620 and it's an OEM module.
The markings on 1 of the chips (the other 3 are covered by stickers) reads:
48LC4M16A2
TC or TG -8E B

So at best it might be overclockable to 133MHz. I still think it's possible that some freak PC-133 32MB module was created, but these should be made when these modules were already low-end, possibly made with stashes of leftover SDRAM chips rated at 133MHz.

These 2 modules I found were both identical and were HP modules, no idea if these would actually be able to run stable at 133MHz, but afaik PC-100 cl2 might run at 133MHz cl3...or it might not.

edit2: I did find an example of a SDRAM DIMM with a whopping total of 16MB 🤣

I want so finish this upgrade ASAP so would these do:

http://www.benl.ebay.be/itm/390260471853?_trk … K%3AMEBIDX%3AIT

or better like Terium suggested:

http://www.benl.ebay.be/itm/Micron-32MB-PC66- … NIAAOSwepZXSWut

Murugan wrote:

I want so finish this upgrade ASAP so would these do:

http://www.benl.ebay.be/itm/390260471853?_trk … K%3AMEBIDX%3AIT

Just to make sure you're aware, that's 168-pin DIMM EDO DRAM, not 72-pin SIMM EDO DRAM which you'll want if you want to keep using the same type as you have right now.

The other link is alright for the PC-66 SDRAM.

Hi archsan

TBH, for me it doesn't really matter if I use SIMM or DIMM. I just want to upgrade it to 64MB. I'll order the 168-pin then.
Just noticed the VGA card in that machine has some empty sockets. Gonna remove it and check which card it is exactly.

That's alright, it's just that, pertaining to previous discussion in this thread, the DIMMs are 3.3V and the SIMMs are 5V.

Also, I just revisited this excellently written website and noticed this important bit:
http://redhill.net.au/b/b-98.html

Single-sided and double-sided RAM […]
Show full quote

Single-sided and double-sided RAM

Generally speaking, boards of this era could accept any of the readily available varieties of 72-pin EDO or fast page RAM, so long as you fitted it in pairs. Common combinations were 16MB with a pair of 8MB EDO SIMMS, 32MB with two pairs of 8MB or one pair of 16MB, and 64MB with two pairs of 16MB or one pair of the rather unusual 32MB EDO SIMMS.
64MB EDO modules were available in theory but incredibly expensive and no-one could afford them. They may have found a home in servers or large CAD workstations but we certainly never sold any, and don't recall seeing one to this day.

The ability of boards to accept SDRAM varied quite a bit. Some of the oldest ones had no SDRAM slots at all. Some had only SDRAM support, the vast majority could work with either type — though very few boards could take both types at once the way a VA-503 could.

However, the vast majority of board up until about this time could only take SDRAM which used 16Mb chips. Note the lower-case 'b' to indicate mega bits, not mega bytes. Most 32MB DIMMs manufactured were double-sided — essentially a pair of 16MB DIMMs mounted back-to-back on a single circuit board — and each side had eight 16Mb chips to make 16MB, or 32MB in total.

Most 64MB DIMMs were single-sided, and used eight 64Mb chips. And this is where the problems start, for most older mainboards do not understand 64Mbit chips and see a standard 64MB DIMM as eight 16Mbit chips. Similarly, they see a typical double-sided 128MB DIMM as sixteen 16Mb chips and report only 32MB.

Please understand that I'm not trying to add confusion or anything, only wanting to clarify as much as possible to avoid wasting time. 😀

Summary, for 64MB RAM, either get:
2x 32MB (8Mx32) 72-pin SIMM (5V) EDO DRAM 60ns
example

_or_ get:
2x 32MB (4Mx64) 168-pin DIMM (3.3V) PC-66 SDRAM 10ns (double-sided or 16 chips)
example (which looks identical to the one in your 2nd link above)

@archsan: your help is really appreciated!
The RAM has arrived at my parents so I'm gonna pick it up tonight and hope the memory will be compatible.

I just removed the VGA card to and it's a Fastware VC963C-3D with S3 Virge On Board chip. There are 4 empty sockets so I'm guessing this is to upgrade the videoram or something?
I tried googling for more info on the card but I don't find much info??

Ya filling the empty memory sockets on the Virge enables you to use higher resolutions in Windows. Honestly as long as it's a 2mb card you should be fine.

Just installed the DIMM memory (IBM 32MB 60ns (4M x 64) 3.3V 76H0275) and it's working yuy!
I just changed the memorysettings to 60ns instead of 70ns in the BIOS. Don't know if it matters much.....
Tomorrow the AWE64 is going in and then the small upgrade is finished.

Found these chips for the Virge on Aliexpress at around 3€ a piece so I'm gonna pass on this one for now since my 486-33 is the only retro PC that is installed ATM.
They'll cost probably more than the card is worth!

Thanks for all the great help lads! I'll keep freshing up my retro knowledge 😀

Installed the AWE64 this morning. I was thinking about putting in the AWE32 Pnp or AWE64 Gold but I ended up putting in a regular one.
Everything is working so it's going on the shelf now 😀
I don't know if I want to spend money on upgrading the vram on the GPU. These chips are quite expensive IMO

Here are the final pics (cable management is a disaster I know!)

Next upgrade: the P3-1Ghz

Thanks for all the help!