Anyone else overclocked Pentium 2 before?

[Keikan]

Ya so i go to cpu database and look at all the p2 400mhz and see that most people have overclocked to 500mhz (!!!!!)

For me I'm sitting overclocked at 448mhz on a P2 400mhz on a Abit BH6 1.1 yes this board is so overclocking friendly :D

I tried to overclock to 466mhz but when i load to the windows 2000 white loading screen with the blue bar and everything, it hangs same for 450mhz.

I heard you could unlock the mutiplier with the SEL 66/100 feature ??? I do not know what that is.....

MY cooling is pretty low stock heatsink on cartridge and one loud case fan at the back

So anyone else overclocked p2 before?

[batboy]

Yes, I've overclocked a couple P-II CPUs in my day.

The BSEL mod won't work for you because that's already a 100 FSB CPU.

The reason you can only reach 4X112 FSB or 448 MHz is because if you go higher than that, the PCI bus is running too far out of spec. Not sure if that mobo supports 1/4 divider at 133 FSB or not. Some of the early BH6 mobos did not have a 1/4 divider. The other thing you might try is increasing the voltage up to 2.2v and see if you can hit 115 FSB for 460 MHz.

[Keikan]

i think i have 133 1/4 i'll have to check

so wat happens if i do?

[batboy]

You can get the PCI bus back in spec if by some miracle you can get it to run at 133 FSB (533 MHz).

[Keikan]

Woh i pushed it to the limit it runs at 466mhz

[Ravsitar]

I used to have and old p2 233 that I'd run at 250 or something with that strange 72 mhz fsb back in the day. The ram I had wouldn't go any faster. stupid pc66 :)

[larva]

This is not a pci speed issue. 113fsb is only 37.3MHz on the pci bus with a 1/3 multiplier, not enough to cause a problem. This is just what people blame when they don't want to quantify (or admit) the real problem.

The problem you are running into is either core quality or L2 cache speed. P2-400s were made for a long time, and over that time faster TAG and data chips were adopted for the L2 cache, and the core quality (and subsequent cpu core clock speed potential) increased dramatically. Early P2-400s only reach 448MHz routinely, later ones will do 480MHz every single time (at an OMG PCI rate of 40MHz :)) and often 500. All you can do is get a good heatsink and increase the Vcore. 2.2-2.3V will be required to maximize the potential of most nominally 2V P2s. Even though your board likely supports the 1/4 PCI multiplier nothing short of radical cooling and massive Vcore is likely to get this chip to 133fsb.

[Keikan]

How you suppose to get a new heatsink for such a old processer and on a cartridge processer

[batboy]

Poor Larva, still in denial about PCI bus speeds. I've had harddrives that puked at 37 MHz, noteably an old Seagate. I put in a 13 gig Maxtor and I was able to run a P-II at 39 MHz PCI bus. PCI bus being out of spec does indeed affect some devices. To claim that 37 MHz won't cause a problem without knowing exactly what components he's running is just plain silly.

Another reason the P-II doesn't overclock as well as the Celerons of the day was because the L2 cache ran off die and at half speed. certainly the later P-II's had more O/C potential than the earlier ones too.

[Keikan]

Alright i got to 496mhz but I couldn't hit 500mhz since the mobo seem to not have 125

[Foxie3a]

mine stops at 464mhz..

but my motherboard doesn't appear to allow me to adjust my Vcore.. :(

Does anyone know for sure? I have a Asus P3C-D

[JaY_III]

if you want to test if your P2's L2 cahce is holding you back, DISABLE it
Turn it off in the BIOS and see if you can clock higher stable. If so, you know that your cache is the problem.....
Even if you can overclock higher with the Cache OFF, dont keep it this way as the system will be alot slower. Its just nice to know what is holding you back.

Also you sig says you only have PC100. that can also be a problem. Set your RAM to the slowest timings when overclocking and speed it up once you get the CPU stable.

I/O voltage. Defualt is 3.3V... 3.5V help stability at higher FSB speeds, and might help your (helps the RAM) Some Abit boards do this by defualt.

As for the PCI speed and HDD's crapping out at 37MHz.. i had an old 4GB quantium that did that also... Every other drive i have had could do at least 40Mhz

Also, do you have the latest BIOS? Can often help

@Foxie3a, what CPU?

[Foxie3a]

P2 400 (4x100)

[larva]

Originally posted by batboy
Poor Larva, still in denial about PCI bus speeds. I've had harddrives that puked at 37 MHz, noteably an old Seagate. I put in a 13 gig Maxtor and I was able to run a P-II at 39 MHz PCI bus. PCI bus being out of spec does indeed affect some devices. To claim that 37 MHz won't cause a problem without knowing exactly what components he's running is just plain silly.

Another reason the P-II doesn't overclock as well as the Celerons of the day was because the L2 cache ran off die and at half speed. certainly the later P-II's had more O/C potential than the earlier ones too.
Poor batboy, still confusing symptom with problem. Just because you at one point bought junk like seagate does not mean his PCI is his problem. With proper system design and component selection, PCI does not generally limit things until 45MHz. But I see these two considerations are simply not known to you.

[Foxie3a]

don't you two usually say to keep things on topic and no flaming on ANY kind? :-p

[{PMS}fishy]

Originally posted by larva

Poor batboy, still confusing symptom with problem. Just because you at one point bought junk like seagate does not mean his PCI is his problem. With proper system design and component selection, PCI does not generally limit things until 45MHz. But I see these two considerations are simply not known to you.

I would hardely consider segate junk.

You and batboy are both confused :)

[Foxie3a]

I've always thought of Seagate as being the cheap stuff? have they changed?