I can't remember the details, but these Semprons weren't they just rebrandings? They should perform just as well as the XP.

I have an old main board a MSI KM2M Combo@6738 and even this main is limited to 266mhz!
I tested its with an AMD Athlon XP 3000 Barton with 333mhz bus speed and with a Sempron 2600+ and it works 😀
MSI's BIOS shows to me the Barton core like an Athlon XP 1900+ but it works and runs well!
It could be the same... You can try 😀

PS:@Phil you said well, the first Sempron generation was a simple rebrand of thoroughbred core!
Only Sempron 3100+ was different, core Paris was a 754 socket CPU 😉

It looks you're in luck. Not every KT133A board supported Athlon XP & Semprons out of the box. Every Athlon XP should work, but it will be limited by 133MHz FSB and low multi. You should get a higher rated mobile processor that use 133MHz FSB and have multi above 15x. But this creates another problem as these boards don't have multi above 12.5x in BIOS. So it might work with higher multi or not. In Windows you can set multi on the fly by some programs.

It looks like the highest multiplier is 12.5 if you set it manually with jumpers. In that case, the fastest CPU is a 2100+ (1666 MHz). However, Soyo lists the 2600+ as the fastest CPU for the board here http://web.archive.org/web/20031202150608/htt … bdesc.php?id=16

Maybe the jumpers are for only those CPUs that are multiplier-unlocked. I assume that setting the multiplier option to "auto" may allow it to recognize a higher multiplier. I won't really know until I get a chance to play around with the BIOS.

I also read that you can mod a mobile Barton CPU by doing something with the pins. Apparently, the Barton XP-M is cooler and is multiplier-unlocked.