Help-When did Intel lock the multiplier?

[penguin]

I have an Dual LX mobo and a pair of 266Mhz slot 1 CPU's. Are they multi locked?

I also have a Dual BX mobo with a pair of 300Mhz Slot 1 CPUs are they locked?

[GunHo]

yep...their multi-locked,,,gotta use the bus speed to overclock.

[Obsolete]

Actually Intel fully locked Multipiers in August 1998. If you CPU's date back before then they are Multiplier limited. Meaning they have a max multi but you can lower it(and in the cause of some 266 you can even use a 3.0x multi).

The first few 400 and 450's on the market could be unlock by the Sel66/100 bios option on Abit motherboards, but intel soon "fixed" that

[krusty the klown]

You can just try a different multiplier - it will either work, not POST at all, or POST at some daft speed like 133MHz. Try the 'next one up' from default.

[Eli]

Obsolete's got it right. Some older PII 266's (including mine right here) can be bumped up to 300 just by upping the multiplier. It has to be one of the easiest overclocks in history.

[penguin]

Thanks Eli and Obsolete
I will give the bump on the LX set to 5X (300). Think they might do 5.5 or 6? the board doesn't officially list those settings but looks like the dips would set for at least 5.5.

[severen]

I got a P2 300 that will run 450 no prob(100x4.5),,Im not sure if the multi is locked or not,,but it doesn't act like it is! It's a real sweet CPU,,it just does whatever I ask of it and never complains.

But in order for me to go above 450 Im gonna have to increase the core voltage and so far it doesn't seem to like that at all. :^(

[penguin]

450 is a great overclock. that's 50% over stock rating.

[krusty the klown]

There was a small batch of P2 300s that would almost all do 450 effortlessly. The multiplier was locked, I believe - 4.5*66. So if your mobo allowed it (and didn't autodetect a 66MHz FSB) you just ran it at 4.5*100 and laughed at the price of a genuine P2 450 http://sysopt.earthweb.com/forum/smile.gif

Here's the nostalgia trip:
http://www6.tomshardware.com/cpu/98q4/981215/sl2w8-02.html

I'd guess that was quite a rare chip, the SL2W8. You never know... the celeron 300a, the P2 300 SL2W8, and the Coppermine 500E could be well worth some money in 60 years time..... your grandkids sitting on your knee asking if you can help overclock their 30000a 256bit up to 45GHz.... well it all started back in 1998 when I had a celeron 450.... but they didn't make a celeron 450 in 1998.... I know http://sysopt.earthweb.com/forum/wink.gif

[Freya]

I think the P133 was the first chip to get the multipliers locked but you can still overclock it by increasing the bus speed.

love

freya

[Eli]

Penguin, the older PII 266 chips have a max multiplier of 4.5x, therefore without upping the FSB you'd be stuck at 300MHz. Still, it's better than nothing.