Cel566 runs @100Mhz only!

[NismoSST]

This is my first post on this fine forum so bear with me please!
I've just got my hands on a Celeron566 and have overclocked it to 850Mhz no problem. What puzzled me was that it wont run with a FSB other than 66Mhz or 100Mhz. I'm not complaining but is this unusual? I thought it might do 75 or 83 before it did 100.
Cheers for any info.

 

[NismoSST]

Oops, sorry pressed post twice! Please ignore.

 

[Nick Stone]

What motherboard? Does it have a soft menu Bios? If you have older components it's possible that some of them don't like running on the PCI or IDE buss at 41mhz. However most will run at 37.5 or 75mhz FSB.

 

[Eug]

Yeah, could be the PCI components. Could be the AGP. It helps to have a listing of your system.

 

[NismoSST]

Ok, here's my system:
Abit BH6 (SS bios)
3DFX velocity100
SBLive
Maxtor15MB (7200)
Maxtor4.3MB (5400)
128MB Ram
Pace Modem (ASA)

Sorry I forgot in first post.
Cheers again!

 

[Nick Stone]

Well if you want to experiment, you might unplug the older Hard drive and the modem if it's PCI, and anything else on those busses one at a time and see what happens. Is that a PCI or AGP Video card? I assume your adjusting the voltage "reasonably" like about 1.6 for 75 and 83 mhz.

 

[Eug]

Hmmm... Dunno about your specific drives, but I've had problems with 5400 rpm Maxtor drives even an 37.5 MHz PCI.

 

[StatsMan]

In the 5400 rpm hard drives I have: Western Digital, Maxtor, Seagate, and IBM, only WD drives works well under 37.5MHz PCI bus. Seagate can run a while but not reliable. Maxtor and IBM just refuse to boot. Not sure about new models.

 

[NismoSST]

Thanks for all the replies, it's nice to know there is support if you need it!
I'm quite happy that the system runs OK with a 100Mhz FSB it must be the non-standard PCI bus speed thats causing the problems. My previous cpu (Cel300a @450) worked OK at all FSBs up to 100 but that was with a different video card and HD setup. That could be a clue!
Thanks again for your help.

Frank.(NismoSST)

 

[BuddyHolly]

A 5400rpm maxtor i have will not run at those pci speeds either. My WD in my big system will them fine.

 

[ErikaeanLogic]

Did you try 105MHz frontside bus? It won't put your PCI that much out of spec(35MHz) and you'll bump up to 892MHz. How do I know this? That's what I did with my 566.