You definitely need the motherboard manual to find out the arrengement, type of chips and jumpering
It is possible that one bank can be upgraded only by a special sipp type chip for 512 kb total.
Being a Packard Bell, it must have a manual somewhere...

Are there solder pads on the motherboard that would let you add the the two extra pin holes?

Please remove the red barrel battery too before it leaks acid all over the board.

The sockets are 32 pin but the wide type...
Dig up the the old Packard Bell ftp site, you might unearth some info

ftp://ftp.packardbell.com/pub/itemnr_ol ... SH/OLDIES/DESKTOP

and

http://pbclub.pwcsite.com/PBFTP/

plus

http://www.uktsupport.co.uk/pb/pbidx.htm

here, jump to:

http://www.uktsupport.co.uk/pb/mb/pbmb1.htm

Anonymous Coward wrote:

Are there solder pads on the motherboard that would let you add the the two extra pin holes?

Please remove the red barrel battery too before it leaks acid all over the board.

thats the first thing I did.

my motherboard appears to be http://www.uktsupport.co.uk/pb/mb/410.htm

it says the cache chips are the same as for the PB430 which says
"Cache memory on a PB430 can be upgraded to 512kB by installing four 128kx8 cache chips (at locations U15, U19, U24 and U30) and one 128kx8 tag SRAM chip (at location U35) "

but I already knew this. It doesn't mention anything about proprietary chips or specific sizes just that I need 5 128kx8 chips...which I have...which are the incorrect width.

I need some help about cache for 486, too...
It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like the shorter portion of a VL-bus. The slot is located aside the CPU slot:


What's the key word should I use on a market search for such cache module? Thanks.

lazibayer wrote:

I need some help about cache for 486, too... It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like […]
Show full quote

I need some help about cache for 486, too...
It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like the shorter portion of a VL-bus. The slot is located aside the CPU slot:


What's the key word should I use on a market search for such cache module? Thanks.

looks like a slot for a COaSt module or "cache on a stick" BUT most of the COaST sticks on ebay are for Pentium machines. I didn't even know any 486 motherboards besides the m919 uses a COaST stick. Using the wrong COaST stick in that such as one ment for a Pentium board could do damage.

soviet conscript wrote:

lazibayer wrote:

I need some help about cache for 486, too... It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like […]
Show full quote

I need some help about cache for 486, too...
It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like the shorter portion of a VL-bus. The slot is located aside the CPU slot:


What's the key word should I use on a market search for such cache module? Thanks.

looks like a slot for a COaSt module or "cache on a stick" BUT most of the COaST sticks on ebay are for Pentium machines. I didn't even know any 486 motherboards besides the m919 uses a COaST stick.

Yea Pentium coasts are easy to find. The slot looks totally different in shape than a Pentium coast slot.

soviet conscript wrote:

thats the first thing I did. […]
Show full quote

Anonymous Coward wrote:

Are there solder pads on the motherboard that would let you add the the two extra pin holes?

Please remove the red barrel battery too before it leaks acid all over the board.

thats the first thing I did.

my motherboard appears to be http://www.uktsupport.co.uk/pb/mb/410.htm

it says the cache chips are the same as for the PB430 which says
"Cache memory on a PB430 can be upgraded to 512kB by installing four 128kx8 cache chips (at locations U15, U19, U24 and U30) and one 128kx8 tag SRAM chip (at location U35) "

but I already knew this. It doesn't mention anything about proprietary chips or specific sizes just that I need 5 128kx8 chips...which I have...which are the incorrect width.

Measure the width of one of the sockets. It will be either 300mm or 450mm. In all likelihood it is a special socket that accepts 300mm dip 28 OR 450mm dip 32. Then its as simple as a bit of google-fu. I'd start with "sram dip 32 450mm 128k x 8 5v"

will do, as a side note whats generally better. having less but faster L2 cache or larger and slower. for example will I get more performance with 128k or 15ns l2 or 512k of say 35ns l2

lazibayer wrote:

I need some help about cache for 486, too... It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like […]
Show full quote

I need some help about cache for 486, too...
It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like the shorter portion of a VL-bus. The slot is located aside the CPU slot:


What's the key word should I use on a market search for such cache module? Thanks.

A similar slot also appears on a Compaq Prolinea motherboard:

Like I said, my PCChips m919 486 motherboard has a slot like that. I had to track down the special COaST module for it. took awhile. it was labeled "for 486 m919 use only" I assume your board has a similar proprietary module maybe?

soviet conscript wrote:

will do, as a side note whats generally better. having less but faster L2 cache or larger and slower. for example will I get more performance with 128k or 15ns l2 or 512k of say 35ns l2

That's not how it works.

Having lower ns is not going to give you better performance.

But what it might allow you is run the system with lower Cache timings. You see unlike RAM which has SPD, the motherboard / BIOS cannot "read" the speed of your Cache.

So check the BIOS and see what Cache settings you have available. It also depends on the clock speed. The higher you go with the FSB the more wait states will be needed.

I'm pretty sure that 15ns is compatible with the fastest timings on a 33 MHz FSB.

I get all my Cache chips from Element14. 9 of them for a 256K Cache, so for your board, 5 should do the trick for 128 KB. Having more cache does very little I found. You just want to avoid not having any.

lazibayer wrote:

I need some help about cache for 486, too... It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like […]
Show full quote

I need some help about cache for 486, too...
It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like the shorter portion of a VL-bus. The slot is located aside the CPU slot:


What's the key word should I use on a market search for such cache module? Thanks.

A little progress on this topic...
I found a picture of this exotic cache card that looks like a good fit.

From: http://ummr.altervista.org/x86gen.htm

lazibayer wrote:

A little progress on this topic... I found a picture of this exotic cache card that looks like a good fit. http://ummr.altervis […]
Show full quote

lazibayer wrote:

I need some help about cache for 486, too... It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like […]
Show full quote

I need some help about cache for 486, too...
It's for FIC 486-GAC-2, which uses a quite odd shape of cache slot that looks like the shorter portion of a VL-bus. The slot is located aside the CPU slot:


What's the key word should I use on a market search for such cache module? Thanks.

A little progress on this topic...
I found a picture of this exotic cache card that looks like a good fit.

From: http://ummr.altervista.org/x86gen.htm

I think I may actually have one of those CPU-like chips, but separated from any daughterboard and with pins and all, very similar to a 486.
Never really knew where its previous owner got it from. But it looked interesting (it had an extra row of pins I think, but spacing was similar to a typical 486 CPU).

The Intel 82385 is a cache controller for 386-class computers; I have a few of them in my collection. I'm not familiar with 82485 but I imagine it's something similar, perhaps adapted for the 486/later architecture.

Info on 82385: https://ia800509.us.archive.org/11/items/bits … ation_Jul87.pdf

A ducument frm Intel about a professional 486 workstation that used a "turbocache module" based on the 82485; unfortunately not much information, no pictures or diagrams. http://www.elhvb.com/mobokive/Archive/Intel/p … kstationtps.pdf

(edit) found a picture of the turbocche module, it's similar to the picture above but definitely not the same http://xhoba.x86-guide.com/en/collection_dive … pu-no225-5.html

When browsing old computers on ebay I found some one was selling a non-working Compaq Deskpro 486 with the Prolinea motherboard that has a similar cache slot. So I asked the seller if he is willing to part it out, and he agreed and confirmed that the module is in working condition.
So I have it; under the Compaq label there is a Sony CXK784862Q-33 chip, and that's the only IC on the module.

Unfortunately it doesn't work with the FIC board, though it fits right in the slot. The computer won't boot at all.

There is another possible choice: CYM9236/9237 cache module, which, according to the datasheet, are designed for UMC491 chipset, so the chances are probably against me again.
The whole story begins with me purposelessly browsing 486 parts on ebay and a motherboard from Olivetti M4 464 S caught my attention. It seems
to have the same shaped cache slot but I can't get much information about the cache module from the listing's gallery.

So I asked the seller if he could take some clear pictures of it, and he kindly did.

That's how I got its model number. I don't have it; the pictures are all taken by the seller and I didn't want to ask him to part out a working combination.

Bought this cache but still not the right one 😵
I hate things that are not fool-proof 😠

I have a Shuttle HOT 419 Socket 3 motherboard. The manual says it can do 512K L2 cache if I have the larger DIPs. I had some 10ns chips. I pulled the old SRAM ( W24257AK-15 94430 ), put in the new chips ( ISSI IS61C1024-10N JV530111L 1901) & made the appropriate jumper changes and got no boot. Put the old chips back in and it runs. Do I have the right chips or is one (or more) of the sram chips likely bad? The lone chip at the bottom is the tag chip.

Also, I have a socket 7 mobo that can accept a COASt module. I found one that works, but it only worked after I removed JP3 from the top of the card. Any idea what that jumper might do?