humm sounds complicated lol.

I don't dare trying this

lol ,don't blame you ,the 1st 4-6 attempts are a PITA!

Adrainhants
Fitting DDR333 to your mbrd isn't a problem ,but you are very likely to have problems running your mbrd to 166MHz FSB.

Your PCI bus would be running at 41.5MHz!, and you would run a VERY high risk of corrupting data on your HDD ,that's assuming that none of your PCI cards stop working at that speed (not permanent).
Also your AGP bus would be running at 83MHz (instead of 66MHz) ,whilst most AGP cards would probably be ok at that it would still be another variable.
Another problem that could occur is that unless AMD produce 266MHz FSB Bartons their would be no bios support for them.Yet another variable.
I'm not saying a Barton wont work on that mbrd but the odds are against you!.

Inccidently an old rig I had upto about 4yrs ago had a similar problem.
It was an old S7 Asus TX chipset & officially only supported upto 66MHz FSB though it had 75 & 83MHz settings.When I plugged a K6-2 350 in it (which is supposed to be 3.5x100) I experimented with 75 & 83MHz FSB (4.5x & 5x multiplier),turned out everthing ran fine at 83MHz FSB.
Had I known at the time the risk I was taking I probably wouldn't of tried it .At 83MHz FSB the PCI/IDE was at 41.5MHz!.It worked like that for about 4-5 mths before I sold it.

Your best bet would be to buy an XP2100 (Tbred B core version,assuming thats supported) ,and raise the FSB to around 150-155MHz & then overclock the hell out of it.
Your current RAM might be able to do that (my PC2100 runs at 152MHz CAS2-2-2-6 ) or you could buy some DDR333.

Btw there's also a good chance that your 1.13 Tbird could run at around 1.4GHz .
Why not try overclocking that 1st?

If you want to find out just your RAMs max speed ,unlock your cpu (Tbirds are easy) ,set the lowest multiplier possible & then raise your FSB until it crashes (I wouldn't exceed 155MHz FSB though).
Bear in mind that even at 38MHz PCI bus HDD data could still be corrupted (though thats rare at that speed),ghost your HDD 1st to be safe

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