Acorp 6VIA85P memory support

sulbert · Fri Apr 11, 2003 9:20 am

The mobo mentioned in subject only recognizes half of the Spectek 256MB DIMM (8 chip, P32M648YAC-75A) although VIA 693A northbridge should support 256Mbit RAM chips

BIOS issue?

Fri Apr 11, 2003 9:08 pm

Very likely. I have a 693A board too, and it supports 512MB SDRAM (16 chips) correctly. I had to update the BIOS to get it recognized, though.

sulbert · Sat Apr 12, 2003 3:08 pm

BIOS upgrade to ver. E (as far as I know the latest version available) didn't help - still only half of the RAM size recognized

Sat Apr 12, 2003 6:28 pm

The official site mentions version D as latest... where'd you get yours from? What's its BIOS string?

sulbert · Sat Apr 12, 2003 9:59 pm

Ver. E can be found here, for example.
BIOS string: 09/01/2000-693-596-SMC-2A6LGX3KC-00
BIOS signon (or whatever it is called): 6VIA85P Ver:E 09/01/2000

apple_rom · Sat Apr 19, 2003 9:57 pm

My lastests bios for this mobo is 20.00 beta3 - http://k6-2.narod.ru/polundra/2000b3.rar
Changes:
1. Tualatin support (need some modding socket on mobo).
2. Add all frequences (66-150) in BIOS with jumpers string.
3. Tweak VIA693A functions, with qualify memory 6via85p will be 2-4 times faster (with CPU up to 800MHz faster even than i440BX mobos).
4. And some another things...
About memory. With my special bios 6via85p can work with 256Mbit memory (256Mb/8chip), but need some modifing DIMM slot (need soldering). "Official" bioses not support 256mbit-technology memory...

sulbert · Mon Apr 21, 2003 8:33 am

Thank you for your answer. What hardware modifications are exactly needed for 256Mbit memory support? Are there any side effects?

TIA
s

apple_rom · Mon Apr 21, 2003 10:19 pm

>What hardware modifications are exactly needed for 256Mbit memory support?
Bad, but pictures:

>Are there any side effects?
Yes - support 256Mbit RAM. But i not tested byself (i haven`t this mobo and 256mbit-memory stick). It`s mean - need testing, but this works.
I know once one way for support 256Mbit-RAM on any chipsets without "special_bios_need" (for example i430TX/VIA VPX, i440BX/LX etc...) but he while not tested (need soldering with some elementes)...

Tue Apr 22, 2003 3:32 pm

The address signals can change rapidly (the memory bus can run at 133MHz) - the wire capacitance and inductance might do weird things (stability problems) - does it work reliably?

sulbert · Wed Apr 23, 2003 5:10 pm

Thank you once again, apple_rom!

But before making any hardware modificactions I want to clearly understand what I'm doing. So I tried to find the VT82C693A data sheet (I know that there is nothing on VIA's website), but only got some brief data sheets, which obviously weren't very helpful.
Does anybody have the data sheet on the hard disk (CD, whatever...) and be so kind and send it to me?

apple_rom · Thu Apr 24, 2003 1:31 am

sulbert
http://k6-2.narod.ru/doki/via693a.rar

sulbert · Thu Apr 24, 2003 8:55 am

Thank you

sulbert · Tue May 13, 2003 8:31 pm

No soldering this time...
The owner of the board managed to swap the memory to a DIMM with 128 Mbit chips (which works just fine).