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Young Micro 486 Cache Layout?

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First post, by TheAdmiralty

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Evening, gentlemen.

Got a quick question. I just recently received my new 486DX2 motherboard - a Young Micro VSF486F/S-3VL. It came to me with 64K of cache in some strange nine-8k-by-8 setup which I can't even find listed anywhere. The only information I can find is over at Stason:
http://stason.org/TULARC/pc/motherboards/Y/YO … ml#.VNaLRMmaSpr
...I'd like to have at least 64MB cacheable, which means I'm looking at 256K of cache minimum. I have easy access to several 32k-by-8 cache chips, but the problem is that there are no cache setups given for a nine-chip (eight plus one tag) layout... hell, they list the jumper settings for 1M but not the chip layout, and they don't have the jumper settings for 128K though I don't really need that information.

Any thoughts on how I could either get either 1M or 256K in nine chips running on this board? Did Young Micro have a webpage back then? - I'm sitting here trying to find them on the WayBack machine right now, but it isn't turning out well...

He took out his hip flask when he reached the page that described how he reached the page that made him take out his hip flask.

Reply 1 of 2, by Matth79

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I'd go by this one instead
http://stason.org/TULARC/pc/motherboards/U/UN … VS486F-3VL.html

The figures on the other one do not make sense - 4 8k chips is 32k not 64k, and while 4 32k is 128k, 4 128k is 512k not 256.
I'd say fill the cache with 32k's and use the 256k setting, the 3 settings with jumpers given correspond to the values for 9 chip! I'd say they are correct, and anything suggesting using 4x 8 bit chips is wrong - this is Pentium, with a 64 bit data bus - it NEEDS 8 x 8bit chips for the data!

Reply 2 of 2, by TheAdmiralty

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I thought the same thing when I'd read that, but I've seen boards do stranger things.
This is the board in question:
http://i.ebayimg.com/00/s/MTIwMFgxNjAw/z/JjcA … 9Sug9n/$_57.JPG
...not my own picture, but good enough to see what I'm working with. I just dropped off an order for ten ISSI 128k 15NS chips; apparently they're going to take upwards of a month to ship here, but I'll stick it out with 8MB of memory until then. The numbers on that page seem a lot more accurate.

My next order of business is to fabricate a new real-time clock to replace the dead DS1287 clone... I'm actually going to send in to have a 1-inch square PCB made with room for a DIP-24 header, pads for a DS1285 (DS127 RTC with external battery and crystal), a crystal, and a CR2032 battery holder. I'm expecting it to work quite well. 5.25" FH SCSI drive should be here on Monday along with the Mach32, so we should be having some fun by the end of the day hopefully.

He took out his hip flask when he reached the page that described how he reached the page that made him take out his hip flask.

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