First post, by einr
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Hi all,
I recently picked up a really beat-up DX4-100 system from a flea market. The motherboard is a QDI manufactured part marked V4895P3/SMT V5.0 and it looks really nice (VESA, button cell battery, etc.) but unfortunately it is completely dead. The PSU seems OK, I've gone through all the usual troubleshooting steps: tried booting with a different CPU, different RAM etc, CMOS reset, etc etc etc... but there's no sign of life whatsoever. The drives don't spin up, it doesn't beep, nothing. Dead.
So I've written it off and ordered another, working motherboard, which is on its way to me as we speak. This new board is an M Technologies R407 E/V which after looking through old Usenet posts was apparently a really controversial board back in the day. Apparently some or all of the boards marked "E/V" have fake cache or a mixture of fake and real cache (they would have 0 or 128K of real cache but have a BIOS hardcoded to report 256K). But unlike PC Chips boards, the fake cache is at least socketed and the board should accept real cache if you install it.
From the photos of the board I ordered I can see that only half of the slots are populated, but I don't know yet if I'm going to receive a board with 128K of real cache or 128K of li'l plastic boxes with legs.
Now for the questions...
Question #1: the defective board has 256K of (AFAIK) real 15 ns cache. I assume I can just take these chips and plop them into the new motherboard? Here's what I don't get though: the CACHE TAG RAM. The new board has a slot for tag RAM right by the eight cache slots. On the broken board though, am I correct in assuming this is the tag RAM chip pictured below? It's marked NKK JAPAN N341256P-15 which is a 15ns 256kbit static RAM so I'm pretty sure that's it, but I feel like I gotta double check.
Question #2: if anyone has experience with these MTI R407e/v boards... Will the modified BIOS pose a problem when installing 256K of real cache? What are the proper jumper settings?
Appreciate any and all help 😎