Thunderbird-multiplier problems

I have an old Athlon Thunderbird 9X100. I decided to overclock it.
I got a bad tip and i matched all L3, L4 and L6 bridges.
When start computer it wil boot at 1050 but win Xp will crash. When I want to restart it after the crash it runs at 900 and all is O.K. I have set voltage to 1,85 on the bridges, and the temperature of CPU is also O.K. I don't know why my Atlon starts at two speeds and I need a solution. The second problem is the crash. It will crash after the loading logo Win Xp but before you see a desktop.

Crashes/reboots usually mean one of three things:
1) Heat. What are your temps under load? Perhaps they are ok in the BIOS when idling but once you start loading up an OS....
2) PSU. What wattage/brand is it?
3) RAM. Try running memtest86 from www.memtest86.com to see if the RAM is bad.

I would also try a bootable OS like Knoppix or Overclockix to see if maybe just your copy of windows is corrupted?

My Athlon burnt, so I'm lookin for a new Athlon XP.