VOGONS

[Help wanted] to make changes to the PCI frequency division for SIS496/497 and IMI SC464

Topic actions

First post, by zwrr

Posted on 
User metadata
Rank Member
Rank
Member

Hello everyone, I have a BEK-P407 motherboard, based on SIS 496/497 chipset, using IMI SC464 clock chip, the motherboard works very stably and the compatibility is very good, especially it has a 4V processor voltage, which can help POD83 overclock to 100 smoothly.

But there is a problem that confuses me, when the motherboard sets the bus frequency to 40Mhz, the PCI frequency is 1/2, which is 20Mhz, I checked the manual of the SC464 and SIS chipset, and tried all the exposed and undisclosed jumper settings on the motherboard, but it can't solve this problem.

I have measured the IMI SC464 pins, frequency jumpers, PCI clock pins and hope someone can help,
1.Is PCI frequency division done inside IMI SC464 and what controls it?
2. What hardware modifications can I make to fix the PCI bus frequency issue?

The attachment SC464.jpg is no longer available
The attachment Jumper.jpg is no longer available
The attachment IMI SC464 Manual.pdf is no longer available
The attachment SIS 496-497 Manual.pdf is no longer available
The attachment BEK-P407 Manual.pdf is no longer available

Pentium MMX233, Zida TX98-3D, 64MB, Riva 128, Aztech Waverider Pro 32-3D, HardMPU-wt

K6-III+550, FIC VA-503+, 256MB, Voodoo3 2000, Creative AWE32, HardMPU-wt

Tualatin-1.4G, QDI A10BM, 512MB, G400, Voodoo2 SLI, Creative AWE64

Reply 1 of 2, by bertrammatrix

Posted on 
User metadata
Rank Member
Rank
Member

I had a quick look at the manual - I'm pretty sure it is JP8 . It has a position for up to or over 33mhz. Set it the other way and see if pci is at 40.

Reply 2 of 2, by Horun

Posted on 
User metadata
Rank l33t++
Rank
l33t++
zwrr wrote on 2024-10-16, 02:42:

Hello everyone, I have a BEK-P407 motherboard, based on SIS 496/497 chipset, using IMI SC464 clock chip, the motherboard works very stably and the compatibility is very good, especially it has a 4V processor voltage, which can help POD83 overclock to 100 smoothly.

Why is your board picture missing so many parts ? All those are populated on the two pictures at TRW...

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Go to top of page Go to top of page
Back to General Old Hardware
Close window
Close window