Celleron 800 on be6

I have an Celeron 800 that I want to run on a be6 instead of the my 366@550. I have the latest bios, but the computer won´t boot. I can´t even reach the bios.
Can the problem be that I have an old converter(370>slot1)?

the slotket is most likly the problem.
make sure it supports FC-PGA processors.

When you changed CPUs, did you change the slotket jumpers to coppermine? That's usually the big mistake most people make. You have to change the voltage jumpers to match your new CPU too. I would leave the third set of jumpers on auto.