• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Please help...2400 OCing problems after unlocking

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.


Mar 25, 2002
Washington State
Anybody got a 2400 to run @ 200FSB?

update to my earlier problem: re-doing the unlock did the trick, but I can't get past the second boot screen at 200fsb, regardless of multiplier, BUT my memory runs 200 24x7 with the 1800... so i'm wondering if anybody out there has had a 2400 run at 200fsb?

I'm in OC purgatory right now. (not quite hell yet)

The new 2400 I bought worked fine when I first fired it up and I tested it to into the mid 2200 mhz range at 1.85 vcore to make sure it was stable at 2200 so I could run it at 11x200.

So I unlock the 5th L3 with some rear window defogger I had left from my 1800 unlocking by making a "U" around the open pit.

Now begins my problems. I'm having SEVERE stability problems even up to 166fsb and a low multi. Sometimes it won't even boot after saving out of bios at 166fsb with a multi of 10!!! I don't know what's happening here, but can anybody shed some light on this? I checked my unlocking work well and I am making good contact with both points and none of my conductive fluid went into the pit.

I think that for now I'm going to pull it back apart, clean off my unlock and run at default multi and low fsb until I can get it figured out.

Any wisdom in this is much appreciated.

Last edited:
More info: I was stable at 147 fsb x 15 with 1.85 vcore when first testing the chip. After unlocking, I'm having a hard time booting up with 12.5 x 133!! The most common thing I'm seeing is that after saving my settings in the bios, the computer just shuts off instead of rebooting. I then have to manually turn off the PSU power for a few seconds and restart. After a few failed post attempts, it will reset my cpu multiplier and then I can post.

Damn freaky weird. Anybody else experienced anything remotely similar to this?
well dont make no sense to me either.
i just didnt want ya thinking people wasnt looking.
my best guess would be to try the unlock again.couse its not posting into the bios tells me the chip is failing.

i wish i had better asnwer for ya tho.look at all your voltages you can and verify it best you can.might be a place to look.dont see how this could be it but im kinda out of ideas for now.
Thanks for the reply. :) I figure I'll clean it up and re-unlock it again since everything was fine before I unlocked it.
yeh just seems weird it to do that.u was able to get 147 fsb @ higher multi.

lower multi should be a given 166 anytime.with a bios flash eliminates the lower multis being the fualt also.all things point to the chip if the voltages are fine.
I look at this thread couple times and think hard about it. I didnt post anything because I don't know what is wrong with it. It is just bizzare to me because I have less better mobo than his and we are use the same cpu, I unlock mine successfully and was able to get pretty high FSB but my KT266a does not have 1/5 divisor so I clean up the cpu and locked it again. I cant loose any data on my HD.
Well, I'm doing *better* than I was. I totally cleaned up the conductive paint and re-applied it. One problem was that at one point some paint got into the laser cut channel, so I had to re-clean. BUT I could still see a *tiny* little bit of the stuff in the channel, no matter what I did to get it out... With that weighing on my mind, I did my "U" again and can run stable (so far) at 166x12.5 BUT no matter how low my multi is, I can't run at 200fsb. I post, but on the "memory" check phase at the very start it freezes up. The funny thing is that this memory totally OWNS 200fsb, and has been running it for a couple weeks now with my 1800.

A theory to be shot at: What if the "U" shape gives the current that needs to go between the two pins a longer route than a straight line and the signal is getting lost at high clock speeds. Maybe?

Second theory: the *tiny* bit of conductive paint still living in the laser channel is now holding me back from the high fsb that I always hit with my other chip.

Any thoughts?
nope, +.02 over which is where i have it now. i even tried running it by SPD but no go. I just ran the cpu at 180x12 and it 3d marked successfully. This is pretty bizarre, but at least re-doing the unlock is giving me stability at relatively high clock speeds.
Have an AIUCB 0241 and have noticed some extra vCore is often required to get this chip to boot on 200FSB wheras on my XP1600+ it was fine to 206FSB.
I have had it boot at 200x10.5 and 200x11, but needed 1.85v for 200x11.
what is your cpu decode set at?? It seems as if the t-bred's require more voltage to reach high fsb speeds than they do to run high clock speeds for some reason.. It could be the way the memory taxes the cpu on high fsb speeds using faast or ultra decode.. I can run 201mhz fsb but it requires not such a high vcore but get this 3.18v on ddr.. and I run corsair cas2 pc3200 and pc3500..
OC detective, yep, I relaxed the timings down to slow but had the same result. I'm going to experiment with higher voltage tonight...

Markodude, that's one big computer collection you've got there. :) I'm running the core at 1.85, so I'll experiment with raising it.

Qwerty, that's some serious mem voltage! I will crank up my memory's volts and see find the sweet spot between mem / cpu voltage. I'm already running the cpu at 1.85 but memory is only like 2.70, I think.

I feel kinda like a noob on the decode thing, 'cause I don't think I've ever noticed any decode setting in my bios. I'll look for it tonight when I get home. Also qwerty, what's your 2600's stepping? AIUGB? This 2400 I have is AIUCB...

The good news is that I think my unlock is fine now, especially after hearing that you two had to do more voltage tweaking to get to 200fsb. My 1800 hit it fine at like 1.8vcore cpu & 2.7 ram. It is an AGOIA...something.

Last night I ran at 180x12 and looped the 3d mark demo all night while I slept. That's progress! :D

Thanks everyone,