Hello,
I don't have such a mainboard, but did you set the jumpers to the 1MB setting (after inserting the chips)?

Thak you for reply. Yes, of course. I've tried all obvious actions. And even trying two different (also tested) sets of cache sticks.

I always thought the TAG has to be more then 256KB for 1MB cache. Usually 64K x 8.

Batyra wrote on 2022-10-30, 08:46:

Thak you for reply. Yes, of course. I've tried all obvious actions. And even trying two different (also tested) sets of cache sticks.

That's weird.
So when you insert the 8 sticks of 128kx8 and close the 2 jumpers the Bios reports 256kb, right?
Is it really 256kB? Did you confirm it with a test program like speedsys?
When you have 256kB working with the 128kx8 sticks, it is very unlikely that the 128kx8 chips are bad. Could be a mainboard or Bios issue I believe.

Batyra wrote on 2022-10-30, 08:23:

Anyone have any clue what can I do? Maybe similar problem?

Hi,
Have you known there's a schematic diagram for a PCI/VLB motherboard based on OPTi Python 82c547/82c546 chipset?
Will it help? Theoretically you will be able to understand whether electrical connections of cache banks are OK.

kixs wrote on 2022-10-30, 08:56:

I always thought the TAG has to be more then 256KB for 1MB cache. Usually 64K x 8.

This was my first guess also. But the DIL28 socket is limiting TAG size to 256K.

Some (rare) mainboards demanded a different TAG organisation like 16Kx16 (or whatever) instead of 32Kx8. These are sometimes hard to find.

Maybe there´s some info in the silkscreen printing inside the socket?

kixs wrote on 2022-10-30, 08:56:

I always thought the TAG has to be more then 256KB for 1MB cache. Usually 64K x 8.

I think that's it.
It seems like that board will support 512 kB L2 cache with eight 64K x 8 plus tag with 32K x 8.

In my Shuttle HOT-433 I use eight 128K x 8 plus tag with 64K x 8.

Disruptor wrote on 2022-10-31, 20:46:

I think that's it. It seems like that board will support 512 kB L2 cache with eight 64K x 8 plus tag with 32K x 8. […]
Show full quote

kixs wrote on 2022-10-30, 08:56:

I always thought the TAG has to be more then 256KB for 1MB cache. Usually 64K x 8.

I think that's it.
It seems like that board will support 512 kB L2 cache with eight 64K x 8 plus tag with 32K x 8.

In my Shuttle HOT-433 I use eight 128K x 8 plus tag with 64K x 8.

Nope.
Obviously for that Pentium chipset 32Kx8 tag size is enough for 1MB cache. He attached the manual.

CoffeeOne wrote on 2022-11-01, 15:46:

Nope.
Obviously for that Pentium chipset 32Kx8 tag size is enough for 1MB cache. He attached the manual.

Oops. Sure. It isn't a 486 xD
Yes, you're right then.
It's because the data bus width is 64 bit and there's just one bank, not two like on a 32 bit 486.

Thank you everyone for replying. Unfortunately no solutions found so far. Maybe some of you have "proper" manual? O knowledge of three chips that are missing?

Batyra wrote on 2022-11-02, 19:06:

Thank you everyone for replying. Unfortunately no solutions found so far. Maybe some of you have "proper" manual? O knowledge of three chips that are missing?

Hello,
Please answer my questions above.

CoffeeOne wrote on 2022-10-30, 08:58:

That's weird. So when you insert the 8 sticks of 128kx8 and close the 2 jumpers the Bios reports 256kb, right? Is it really 256k […]
Show full quote

That's weird.
So when you insert the 8 sticks of 128kx8 and close the 2 jumpers the Bios reports 256kb, right?
Is it really 256kB? Did you confirm it with a test program like speedsys?
When you have 256kB working with the 128kx8 sticks, it is very unlikely that the 128kx8 chips are bad. Could be a mainboard or Bios issue I believe.

When you put 1MB and jumpers are set as for 256 it recognizes 256... when jumpers are set to 1M there is "No cache".
Also the motherboard recognizes CPU (Pentium overdrive 133) as 100... but test proove it works as 133 - so motherboard issue.

Batyra wrote on 2022-11-02, 20:39:

CoffeeOne wrote on 2022-10-30, 08:58:

That's weird. So when you insert the 8 sticks of 128kx8 and close the 2 jumpers the Bios reports 256kb, right? Is it really 256k […]
Show full quote

That's weird.
So when you insert the 8 sticks of 128kx8 and close the 2 jumpers the Bios reports 256kb, right?
Is it really 256kB? Did you confirm it with a test program like speedsys?
When you have 256kB working with the 128kx8 sticks, it is very unlikely that the 128kx8 chips are bad. Could be a mainboard or Bios issue I believe.

When you put 1MB and jumpers are set as for 256 it recognizes 256... when jumpers are set to 1M there is "No cache".
Also the motherboard recognizes CPU (Pentium overdrive 133) as 100... but test proove it works as 133 - so motherboard issue.

Hi, OK:
for this case:
"
When you put 1MB and jumpers are set as for 256 it recognizes 256
"
Is the 256kB cache working in this case? Confirmed by speedsys?

CoffeeOne wrote on 2022-11-02, 22:28:

Is the 256kB cache working in this case? Confirmed by speedsys?

Yes

Batyra wrote on 2022-11-04, 11:20:

CoffeeOne wrote on 2022-11-02, 22:28:

Is the 256kB cache working in this case? Confirmed by speedsys?

Yes

Hi, then I assume (to 99%) that your cache chips are good!
So I believe it can only be the jumper settings. I mean it could also be the case that the boards works fine with 256kb, and not correctly with 1MB, but that is unlikely for me.

Problem solved!
I've tried different BIOS... it was from exactly (99%) the same motherboard from the same manufacturer and chipset but with socket 5 not socket 4... Revision of bios was the same - I was sure it's identical but after change all started to run!

It recognize my 133 overdrive as pentium 100 but it runs like it should... I think I'll ask someone who knows how to deal with micro-codes or how it is called to change it to be named properly!

Meanwhile - thanks to everyone who tried to help!

Now to the benchmarks 😉

Nice work on getting the cache working!

I’ve been meaning to chime in on this thread, as I own the Socket 5 version of this board.
In fact, if you got the BIOS from TRW, I dumped it for their archive.

One note about the Elegance P90’s BIOS that might be of interest to you: on the Socket 5 version of this board (and presumably, on your board with the appropriate adapter), you can run a WinChip, WinChip2, and even a POD MMX without issue. This is not the case for most Pentium/VL BIOSes.

I have had issues getting 1MB cache working on mine, but I presume it’s all jumper quirkiness.
Do you mind sharing your jumper settings? I am curious to see if I can get the same results on this board’s Socket 5 brother.

Great job, and I hope you enjoy this board! Socket 4 and VLB is a fun/weird/quirky adventure of its own!

kixs wrote on 2022-11-09, 07:11:

Now to the benchmarks 😉

x2