why can't i get fsb over 75mhz?

Snugglebear · Post by **Snugglebear** » Tue Sep 03, 2002 1:51 am

600mhz was the approximate theoretical limit of the mendocino core. I was never able to get past ~630 with my 466s. Also consider that a 75mhz FSB equates to a 37.5mhz PCI spec, which is at its upper bound. Most PCI cards and disk controllers get funky above that point, if not already.

Post by **Derek** » Tue Sep 03, 2002 7:16 am

The multiplier is locked. Changing the option in the BIOS does nothing.

Post by **Derek** » Tue Sep 03, 2002 2:57 pm

The ones who achieve a Front Side Bus of 124MHz or more are doing so with Pentium 3 processors installed.

Edit: There is no 'set' limit for the Celeron's overclocking capability. It varies from chip to chip.

Snugglebear · Post by **Snugglebear** » Tue Sep 03, 2002 3:33 pm

The celerons do not have a set limit. What they do have is a design that is only capable of going so far before the speed is too high for some component to function properly. Accross a range of chips, in fact the entire set of cores, these limits tend to fall within a few % of one another. Hence when I say ~600mhz is the max for the mendocino cores, it means that most people will not see results too far over that mark. It means that some section of the chip is incapable of operating at 600mhz because the clock time is too small for the circuit to work. Having some extravagant cooling solution may up this max speed some, as transistors are more efficient at lower temps, but then you're still not going to get much more.

Now, each chip is slightly different. Why? Because while they're all Mendocino cores, the celerons we use were produced at different factories using different parts and slightly different masks. Those variations can mean a god 5-10% difference between chips.

RRLedford · Post by **RRLedford** » Thu Sep 05, 2002 11:53 pm

DRD,
You can also go & get some Cele-1/366 chips and push them up toward the 110-124Mhz FSB speed (550-600Mhz).

Post by **Derek** » Fri Sep 06, 2002 7:56 am

DRD wrote:question; does the fsb speed relate to the hdd controller speed? ie- ata66 when fsb is running @ 66mhz. does upping the fsb also up the ata speed?

There is no direct correlation between the two, but having your hard drives on the HPT controller may limit your clock speed.

Don't ask why

g0fvt · Post by **g0fvt** » Sat Oct 19, 2002 8:02 am

In the old days of peltiers and watercooling on my BP6 with dual 466 it would POST at 7*92 Mhz but never ran at that clock speed... it ran at 7*80Mhz fine... my northbridge was cooled by a fan blowing in roughly the right area....

Machine runs with OEM heatsinks and fans now at 7*75Mhz... not as fast but stable and reasonably quiet...

Watercooling will be transferred to my VP6 soon, it is dual P3 933s @ 1155... would go to 1200 ish but second stick of memory doesn't like it.

I will post pictures of my coolers if they interest anyone... easy to build and never leaked!