Slow running AMD Athlon XP2600+

[Knuttyman]

I've just installed a 2nd hand AMD Athlon XP2600+ which carries the correct AMD designation. The M/B is Abit KD7 RAID (266FSB) which supports this CPU. My PC tells me it's running @ only 1.6MHz instead of about 2.2MHz, & it's running cooler than my previous XP 2000+ CPU (1.67MHz) so slower speed appears to be confirmed.
Is there something I should have done to reset the M/B or BIOS? Can anyone advise me?

[Neon]

Be aware there are 3 common Athlon XP 2600+ models.
AXDA2600DKV3C - is least common, and only runs at 266FSB (16x 133 = 2133 MHz)
AXDA2600DKV3D - runs at 333FSB (12.5x 166 = 2083 MHz)
AXDA2600DKV4D - runs at 333FSB (11.5 x 166 = 1917 MHz) - It has more L2 cache, which is why it has lower frequency, but same performance rating

Most likely, you have the -3D (middle above), but need to change the FSB from 266 to 333 in the BIOS.

Make sure that the BIOS is up to date, in order to support that CPU.

[Marcin]

I'm not sure if KT400 support CPUs with FSB 333 MHz. There was ABIT KD7A based on KT400A which does support them.

Fragment about KT400 chipset from VIA web site :"... With a 200/266MHz processor bus and supporting DDR200/266/333 memory..."

If not support then try to use overclocking function in BIOS ?

[Neon]

Abit's BIOS update page for KD7-RAID seems to indicate support for 333 FSB.

Via KT400 may not officially support that, so it may indeed require overclocking.

[xrror]

Worst case if the chipset doesn't like the required FSB to run your chip at full speed. "Just" need to do some Athlon XP bridge modding. Though VIA KT400 should be fine for any official speed?

You can look up your current chip at http://fab51.com/index-e.html and see where you stand.

While if you have to go this route, it may seem daunting. But be glad! The Intel route offers no alternative... It's too bad AMD "fixed" the Athlon64 era where bridge mods no longer work.

AthlonXP you could practically make any chip you needed in a pinch =D