75 mhz

[duncan]

I have a tx98 r2 motherboard with sis 5598 chip set. I have jumper settings in the manual for adjusting cpu speed to 66mhz.
It states in the manual, 75mhz/83.3 bus frequency is not in regular specification, therofore it is not reccomemnded to use it.
I would like to set the bus to 75mhz (amd k6 233). Can anyone help me with the settings or more info on this subject.

[Peter M]

The SiS 5598 is officially rated 75 MHz, and as long as the board implements the 33 MHz PCI feature correctly, nothing's overclocked.

Most boards implement 83 MHz as well, and so far, I found the 5598 to be perfectly stable at that speed - as long as the board's cache chips are fast enough. (My experience based on PC-Chips M571, which runs perfectly well with Cyrix 83 MHz 2.5x processors.) Compaq even uses a 83 MHz clocked 5598 board officially in the 2266 or 2286 (can't remember).

Regards, Peter

[duncan]

Sounds good, Peter... but I need the actual jumper settings for the mb. there are three jumpers sw1, sw2 & sw3. the 5omhz, 55, 60, &66mhz are described in the manual ... but not 75 or 88 ????? thanks for your responce

[Peter M]

In that case, it's about time you get a little more specific about what motherboard you have. Brand and model number would be nice, then let's see if I can point you to the correct information.

As said before, your particular motherboard might or might not implement 75/83 MHz at all, or correctly.

Regards, Peter

[bighammer]

if you have the manual.
read it and look where the jumpers are to get the spec'd bus's.
Then look what jumper positions aren't used.
If you don't have the manual, maybe they are marked on the mobo.
have fun

[duncan]

I decided after a few tries at non standard settings to forget the 75mhz. I however got a noticeable speed increase by turning most of the advanced settings (award bios) down as far as they would go and upping the video refresh (onboard) from 40mhz to 70mhz. Would still apreciate any specific settings for 75 or 83mhz. The board is generic - the manual shows up on the net if entering J-TX98 R2 (sis 5598). thanks for prevoious responces.