Edited later today:
Quote:So basically what was discussed before was that since a single chip V4 was able to be upgraded to 64 megs, if someone were to get the same speed memory chips but double the amount, it should theoretically be able to handle 128 megs instead of 64? When the V4 was upgraded, did it require a bios hack to recognize the added 32 megs or was it just a swap and it worked?
A BIOS hack was required for the Voodoo4 in order to make use of the all 64Mb RAM (credits to Mikulaish) and another type of BIOS change should be required for the Voodoo5 after upgrading the memory.
Quote:right, so based on that, you could put a 128 megs on a V5 (64 for each chip) and have it work then correct? If one were to find the right match up for memory.
It's not that easy; after you un-solder the RAM from the Voodoo5 and from the 2 donor cards, and then after you solder the double-sized RAM on the 3DFX PCB you will still need to do some hard-wire with additional lines because the 4M x 32 chips have a slight different pinout (you have to connect 1 suplementar adress line from each RAM chip) and you might need to do a BIOS hack too.
Quick example: The K4S283232E memory chips from Samsung are perfect candidates for swaping the RAM of a Voodoo5. 16Mb with 32bits per chip, 86 pins TSOP (II) SDRAM, the same as the 8Mb/32bits K4S643232C Samsung chips that we have on many VSA-100 cards by default, but with double capacity. And the pinout is compatible, so you could solder them on our 3DFX cards, all but with 1 exception: see on the datasheets that the orriginal RAM chips have at pin 21 the NC (no connection) and the PCB has no trace there to use the pin, but the memory chips we want (and we need for having 64Mb per each VSA-100) have at pin 21 the line A11 (adress line). In conclusion, you need to solder 1 wire to pin 21 as a PCB trace replacement to make proper use of the extension of RAM.
Back here in Romania I had the opportunity once to buy the ideal doner cards for this job (they were 2 nVidia Quadro's with SDRAM, 4 chips, 64Mb) but It was anything but cheap (40 euro for 1 piece). Maybe someone else here can get the RAM and perform the modding...