How to lock PCI and AGP at 33 and 66 MHz?

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--- How to lock PCI and AGP at 33 and 66 MHz?
https://www.forum-inside.de/topic.cgi?forum=14&topic=27

-- Veröffentlicht durch Webspacemail am 23:29 am 4. Dez. 2002

mhhh... = well please :-)

-- Veröffentlicht durch NWD am 14:26 am 30. Nov. 2002

yep i have heared the same ..

NForce AMD and most P4 Boards have this lock

but no VIA-chipset based or AMD-chipset based boards can do that

-- Veröffentlicht durch KS am 22:33 am 29. Nov. 2002

Why don't VIA do it? :(
I heard that Intel m/b could do it.
You mean any m/b based on NForce2 chipset can do it?

-- Veröffentlicht durch HellerSebastian am 1:18 am 29. Nov. 2002

Is your board a via based board?
if it is not nforce board you could not fix the apg/pci clock

-- Veröffentlicht durch NWD am 22:33 am 25. Nov. 2002

oha dont know if it would work

i have heard about a P4- Mobo mod where someone had changed the Clock generator to get higher Frequencies .. and there are P4 Boards with a locked AGP / PCI..

I think in general it can also be done for AMD MoBos

but i wouldn try to modify a board in that way ..

-- Veröffentlicht durch KS am 22:27 am 25. Nov. 2002

Crazy idea, perhaps.

If I had another clock generator (the same family), I would de-solder PCI, AGP pins of the one on the mainboard and disconnect it. Then I replace those pins with the second clock generator (and other necessary pins e.g. Vdd) and program FS0:3 to fix it at 100/33/33.
Doing this will enable us to overclock the CPU and RAM at any speed without affecting PCI and AGP at all. Do you think so?

An appropriate approach is for m/b manufacturers to incorporate 2 clock generators for this purpose.

-- Veröffentlicht durch darkcrawler am 12:05 am 18. Okt. 2002

-- Veröffentlicht durch NWD am 20:26 am 29. Sep. 2002

i said..

BIOS or not ..

-- Veröffentlicht durch KS am 20:18 am 29. Sep. 2002

I read the datasheet of the clock generator which says that the divisor (any numbers) could be set via I2C by setting certain bits to the registers. This would make it possible. But I don't know how to do that. I guess it got to be something that is hidden in the BIOS.

-- Veröffentlicht durch NWD am 16:41 am 29. Sep. 2002

hmm..

restarting while booting can also have other causes .. ( i.e. too high RAM Frequency or instable PowerSupply )

if your mainboard has this function it should be in your BIOS or there are some jumpers on the board ( see manual )

but normally the AGP / PCI is set by the FSB

-- Veröffentlicht durch KS am 15:06 am 29. Sep. 2002

I think that the main source of my problem in overclocking is the instability of the PCI/AGP bus i.e. the PC does POST correctly but the OS won't boot up (sometimes the OS is booting and the PC restart itself over and over again). At the freq between 101-130 and from  134+, the PCI and AGP freq deviate from 33MHz. I heard that ABIT m/b could implement the PCI/AGP freq locking. IS that possible in other m/b e.g. ASUS, ECS?