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Detecting external cache

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First post, by tincup

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I installed eight 32k 15ns cache modules plus the associated tag chip, set the jumpers to 512k, and booted to W95a with no problem. Motherboard is Elite Group UP8811A v10 rev 3.6.

But I don't see the external cache amount displayed anywhere - during post there is no specific line, just basic ram 640 conventional ram. In bios, cache is enabled [I have it set to 'automatic' with 3-2-2 timings] but the bios doesn't actually display the actual amount of external cache present either. Bios is Phoenix 4.04

I'm assuming that the cache is working since the system boots and runs fine so far - perhaps even snappier. But should I be able to see somewhere the amount of cache the system detects if it is?

Reply 1 of 8, by RacoonRider

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Run speedsys or cachechk.

Personally, I like speedsys better because of a nice diagram in the bottom right corner. The upper step of the ladder depicts L1 cache speed, the next - L2 cache speed and so on... The X axis is logaryphmic and depicts amount of cache, the Y axis depicts speed.

Reply 2 of 8, by JaNoZ

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Ehmm. 8x 32k gives you 256k, not 512k.
You should have 8x 64k or 4x 128k (1 mbit) sram for 512k cache.

Reply 3 of 8, by tincup

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Oops, yeah it's eight 64k modules. And I'll grab speedsys/cachechk and see what it says - thanks

EDIT: correction again - it's 8x 32k cache = 256k NOT 512k. I misidentified the chips.

But the problem is that neither cachechk nor speedsys detects any external ram. I tried various jumper setting for 256k [as well as 512], disable/enabled cache write back in bios, and while the system boots I don't see cache detected. A quick test of a few borderline games doesn't suggest cache is running either.

Fake modules? It was a very inexpensive set of Winbond W24257AK-15 with TAG... Or still missing jumpers settings..

Reply 4 of 8, by RacoonRider

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Could you please attach a speedsys pic?

Reply 5 of 8, by tincup

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hmm, I have my 486 and cache issues spread out over a couple of threads which is a mistake.

After deciphering all the jumper/cache info printed directly on the motherboard [I'm just picking up the lingo and abbreviations with cache stuff] I realized my TAG chip was not the proper kb - I need a 32k TAG to run 2 fully populated banks of 32k dips [256k total] or an 8k TAG for just one bank [128kb]. The TAG I have seems to be 16k [Aster AE88128-15]. So I can't run either configuration yet.

A new 32k tag chip is on it's way and should arrive later in the week. If I continue to have issues I'll post a a speedsys screen.

On a positive note I did succeed in upgrading to 2mb video ram by cannibalizing a pair of ram chips off a Cirrus Logic 'donor' card I got cheap off eBay - Speedsys detected the extra ram, nice. 2mb will do the trick for this machine.

Reply 7 of 8, by tincup

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32k Tag chip arrived. Set cache jumpers for 2 banks @ 256k [8x 32k chips]. Booted but hung during POST after the usual first lines. System initialized 256k cache so may be on the right track.

Tried clearing/reseting bios, disabling L2 write back, and alternate jumper settings.

Any ideas why it hangs at post?

EDIT: Booting to W95 with alternate jumpers [no cache initialized] Cachechk says "seems like only 1 cache?!" and it's operating at 20ns - This must be the on die cpu L1. My external cache is 15ns should it be 20ns like the cpu?

EDIT 2: Problem solved. A damaged cache chip. I was able to boot with one bank @ 128k using the 32k TAG even though the diagram printed on the mobo said it needed to be a 8k unit. Isolated the bad clip pin [my own previous 'handiwork' practically severed a corner one] - so a couple more bucks to eBay...

All cool with Cachechk/Speedsys. 128k L2 really smoothed out Aces Over Europe which had been just a tad laggy. Nice. With another 128k enabled I'll be set and ready to tackle conventional memory jazz.

Reply 8 of 8, by tincup

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Installed fresh set of NKK 32k cache chips and rig now running like a top - thank you Ukraine! Cachechk/Speedsys now report cache as expected though I did have to boot to dos to get them to operate properly. And the IC extractor gizmo I picked up makes the work quick/easy with no bent pins..