Computer Overclocking question

Hopefully someone can help me out here. I’ve got a Abit VH6-T mobo with a 1.3 ghz Celeron II (100 FSB) overclocked to 1.6 ghz at 123 FSB. My problem is once I hit 124 the computer won’t even POST. It’s not a voltage, heat, RAM, or any other component problem. I had a 950 celeron chip running at 129 FSB around 1.25 ghz on the same mobo. The thing is once I hit 124 the multipier automatically adjusts from 1/3 to 1/4. Could that be what is causing my computer to not boot at or above a FSB of 124? Every report I’ve heard of people with 1.3 ghz Celeron’s can get them to at least 1.7 with no problem. I’d like to try and get that extra performance if at all possible. Thanks in advance for all your help.

Just because other people have managed to overclock their CPU’s higher than your is no guarantee that you’ll be successful. In general, the later you buy a CPU at a given clock speed past its initial appearance on the market the better chance you’ll have at overclocking.

Remember that there is no difference between a P-III 800, 900 or 1000 (1Ghz) chip. They are all identical. When a fabrication plant starts churning out CPU’s some are naturally better than others. Each chip is tested at the end of the line and if 800 is the best it can do reliably it gets toseed in the 800 box. If it is stable up to 1000 then it goes in the 1000 bin for sale at a higher price. Eventually as the fab gets its act together most chips coming off the line can operate at 1000. Since there is still a market for the 800 chips they take a certain percentage, turn down the speed and toss it in the 800 bin. So, when you buy an 800 chip and 1000’s have been in the market awhile the chances of successfully overclocking your CPU are pretty good. Buy a 1000 when they are new and chances are you will not be able to overclock it very much.

Since you have already tossed out any other issue such as voltage and the like I suspect this is your problem. You simply have a chip that becomes unstable above 1.6Ghz and there really isn’t a thing to do about it (you might try fiddling with the voltage but that is potentially dangerous to your CPU if you’re not careful). Also, if you can manually separate your ISA bus speed from the FSB you might take that down a notch (I know you said expansion cards weren’t the problem but you never know…not all motherboards can do this however).

Oops…I also meant to mention that even if you buy your CPU at a later time thinking you have a better shot at overclocking you still might get an old one. Many stores endup with old stock sitting on their shelves but sooner or later they’ll manage to sell it. I’m not sure if there is any reliable way to tell how ‘old’ your chip is even when you buy it new.

By process of ellimination, I’d say if the only thing changing is the multiplier, then that’s the trouble, and you’re just gonna have to stick with a 123 FSB.

She jus’ canna take no mo’, ca’p’n!

Oops, I’d a lot more to say, but on preview, Whack-a-Mole’s already said it.

tiki man, what are doin messin with your cpu…you know better. This is a far stretch from our days of messin with Netbus, you know that right?

Hmm. Things don’t look good for you. You say you’ve already checked out the RAM, but just to make sure, have you relaxed the CAS settings?

As a last-ditch suggestion, perhaps you could try raising the FSB still further to 132. With a 1/4 PCI divider, 132 would put things at a nice, proper 33 MHz on the PCI line.

However, I’ve never heard of a PCI device failing at 31, and when everything is already happy way up at 41, I can’t see this really being the source of the problem. Nevertheless, it can’t hurt to try.

Does your AGP divider also change at the 124 setting?