I've just read that HT is not activable on early 5150s (like mine) not because of the BIOS, but because Dell shipped them with a "crippled" 3.06 GHz P4 CPU that had HT disabled at the hardware level.

Dell is now shipping new 3.06 GHz P4s with HT.

If you have an A24 BIOS installed and you don't see a menu to turn HT on, it means that you have an old crippled 3.06 GHz P4 (like me

For more info see here:
http://www.dell.com/us/en/gen/corpor...-23-rr-000.htm
and/or the Inspiron/BIOS forum on dell.com:
http://forums.us.dell.com/supportfor...d.id=insp_bios

I think I'll never buy a Dell again in my life...

Ciao,
Emanuele.