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First post, by Cga.8086

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since there are motheboards with fake cache that dont say write back on the chips
how do you detect if cache is real or not?

i know there was a DOS tool to run that checked that, but i cant remember the name, anyway i used it once long time ago and did not understand what the screen was showing as output.

can anyone explain?

thanks

Reply 1 of 46, by cj_reha

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Use CACHECHK, when it is finished it should show whether it's real or not.

Also not many boards past the 486 era used faked cache as there was no real gain from it besides being scummy (cache prices dropped in the Pentium era)

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Reply 2 of 46, by BeginnerGuy

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It's been a number of years but I dont recall ever seeing a socket 3 board with fake cache that was socketed. All of the fakes I used to come across had that write back bs on them and were soldered directly to the board, this way removing even the costs of the sockets.

If it looks real and is socketed I'd be surprised to see a fake, but I dont know everything, let CACHECHK answer for you !

If you need help with the output just post it here, there's another program with simpler results but the name isnt coming to mind right now. Maybe somebody else knows.

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Reply 3 of 46, by Cga.8086

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thanks all, i suspect it has fake cache because of all these things
im playing doom1 with a dx2-66 intel, it feels like 20fps, playable. but

Cache is soldered to board directly
There is no write back on cache chips
The jumpers for cache dont exist, its all off
The manual has specific settings for cache and none is all off.

the board name only says av-8540
and it has the same schematics as
http://www.elhvb.com/webhq/models/486vlb3/tk8498.htm
F4DXL-UC4D or TK 8498F

jumperss.jpg
jumperss2.jpg

Reply 4 of 46, by BeginnerGuy

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That's a bad sign. A search for the part number on those chips brings up a bunch of hits that would indicate its at least pretending to be a real part, but the following link is from a person who found those same parts as fakes in his board:

http://www.vcfed.org/forum/showthread.php?422 … cache-486-board

run cachechk and show us the results 😢 .. I hope you didn't get ripped off. 20FPS in DOOM doesn't seem too terrible to me, if you have a good vlb video card I would expect higher fps though.

Can you imagine all the poor saps back in the 90s who got tricked by these boards and paid full price? I remember a few people ordering their boards and telling the sales person not to try to screw them with fake cache, and still boards with fake cache would show up. Trade shows with discount boards were another place to find piles of boards like this. I bet it says it has 256k in the bios or at post too even if it's fake 😠

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Reply 5 of 46, by appiah4

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cj_reha wrote:

Use CACHECHK, when it is finished it should show whether it's real or not.

Also not many boards past the 486 era used faked cache as there was no real gain from it besides being scummy (cache prices dropped in the Pentium era)

I've seen too many fake cache PCChips boards to say S5/S7 systems rarely had fake cache..

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Reply 7 of 46, by Gered

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BastlerMike wrote:

Haha...Look at U11... It ist soldered in backwards!

🤣 , I guess that probably answers the question about it being fake cache or not. That really sucks. 🙁

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Reply 8 of 46, by bjwil1991

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BeginnerGuy wrote:

It's been a number of years but I dont recall ever seeing a socket 3 board with fake cache that was socketed. All of the fakes I used to come across had that write back bs on them and were soldered directly to the board, this way removing even the costs of the sockets.

If it looks real and is socketed I'd be surprised to see a fake, but I dont know everything, let CACHECHK answer for you !

If you need help with the output just post it here, there's another program with simpler results but the name isnt coming to mind right now. Maybe somebody else knows.

There were some PCChip motherboards that had the fake cache on the board and they modified the BIOS tricking it to "think" there is Level 2 cache installed. I had a 486 motherboard from 1994-2012, a PCChips M912 v1.7 that had real L2 cache installed by my dad. My Packard Bell Pack-Mate 28 Plus doesn't have L2 cache installed (games and programs require L2 cache to run properly and faster).

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Reply 10 of 46, by Cga.8086

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BastlerMike wrote:

Haha...Look at U11... It ist soldered in backwards!

mother fuckers!!!!
i will check if L2 cache is even an option in the bios
because if not, there is no point on taking the fake out, puting sockets and placing new cache

Reply 11 of 46, by bloodbath2you

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Cga.8086 wrote:
mother fuckers!!!! i will check if L2 cache is even an option in the bios because if not, there is no point on taking the fake o […]
Show full quote
BastlerMike wrote:

Haha...Look at U11... It ist soldered in backwards!

mother fuckers!!!!
i will check if L2 cache is even an option in the bios
because if not, there is no point on taking the fake out, puting sockets and placing new cache

Looks like there are real traces, doesnt matter if that chip is plugged backwards because its just a dummy chip.

i'd try if money isnt a problem, you could pick some solder and socket there.

Reply 12 of 46, by Pabloz

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bloodbath2you wrote:
Cga.8086 wrote:
mother fuckers!!!! i will check if L2 cache is even an option in the bios because if not, there is no point on taking the fake o […]
Show full quote
BastlerMike wrote:

Haha...Look at U11... It ist soldered in backwards!

mother fuckers!!!!
i will check if L2 cache is even an option in the bios
because if not, there is no point on taking the fake out, puting sockets and placing new cache

Looks like there are real traces, doesnt matter if that chip is plugged backwards because its just a dummy chip.

i'd try if money isnt a problem, you could pick some solder and socket there.

I have a pc chips board, before my m919 and it had the same problem, fake cache without a socket, directly soldered to the board.
And when i tried to find compatible cache memory it was difficult to find in my city, only on ebay

besides i remember i gave up because i din´t know exactly the memory specification, i think there was a brand name ISSI that was compatible but the amount of ram in each.. i never knew

Reply 13 of 46, by probnot

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bloodbath2you wrote:
Cga.8086 wrote:
mother fuckers!!!! i will check if L2 cache is even an option in the bios because if not, there is no point on taking the fake o […]
Show full quote
BastlerMike wrote:

Haha...Look at U11... It ist soldered in backwards!

mother fuckers!!!!
i will check if L2 cache is even an option in the bios
because if not, there is no point on taking the fake out, puting sockets and placing new cache

Looks like there are real traces, doesnt matter if that chip is plugged backwards because its just a dummy chip.

i'd try if money isnt a problem, you could pick some solder and socket there.

You'd need to buy sockets for all the chips. Also, buy some jumper headers. AND reflash the BIOS to actually support the real cache. I guess it depends on how much time+money you want to spend on the board.

Sockets: https://www.digikey.com/product-detail/en/on- … 50-5-ND/4147600
Jumper headers: https://www.digikey.com/product-detail/en/pho … -1749-ND/950877
Jumpers: https://www.digikey.com/product-detail/en/sul … 9337-ND/2618262

I have no idea where you would find the BIOS update, but I'm sure someone here might know.

Reply 14 of 46, by BitWrangler

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probnot wrote:

AND reflash the BIOS to actually support the real cache.

Ohhh, I missed that detail with one board... tried 3 different COAST modules in it, had fake cache on the board, connected to nothing, the traces went round in circles... if it resurfaces, I'll have to see if the BIOS makes any difference.

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Reply 15 of 46, by gerwin

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I have pretty much the same motherboard, but with a green colored PCB and 256kB of real cache in sockets.
Topic: 486 VLB UMC-Chipset, what is it? (Has some benchmarks too, on page 2)
Photo: http://www.imagebam.com/image/f14a75319062935

--> ISA Soundcard Overview // Doom MBF 2.04 // SetMul

Reply 16 of 46, by Cga.8086

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gerwin wrote:

I have pretty much the same motherboard, but with a green colored PCB and 256kB of real cache in sockets.
Topic: 486 VLB UMC-Chipset, what is it? (Has some benchmarks too, on page 2)
Photo: http://www.imagebam.com/image/f14a75319062935

it is almost the same board, and looks very solid too, it is identical to yours, there is just a few components that mine does not have and i dont know what they are for
jumpers i know, but there is a couple capacitors and some orange things missing

maybe they are needed for real cache?

TK8498_F_Mainboard_Fullzoom.jpg

Reply 17 of 46, by BitWrangler

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In my experience, the UMC cache chips were usually real actually. You do seem to be missing a Keyboard Controller chip.

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Reply 18 of 46, by gerwin

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Cga.8086 wrote:

...there is just a few components that mine does not have and i dont know what they are for...

Is your board missing the Voltage Regulator? This item is shown in the photo below the two large red arrows. It has three legs and is also fixed with a screw. This circuit was often left out on 486s to save cost, but it means only 5 Volt CPUs are supported, no 3,3V ones, unless you add the components yourself.

BitWrangler wrote:

In my experience, the UMC cache chips were usually real actually. You do seem to be missing a Keyboard Controller chip.

It was always like that, very sure nobody removed anything since the case was assembled in 1995. My keyboard works fine anyways?

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Reply 19 of 46, by BitWrangler

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Must be built into chipset on that one.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.