Die-locked CPUs
Starting from week-39 of 2003, Athlon CPUs have certain bridges locked via the
core, so modifying these bridges does not affect operation at all. The
approximate date ranges are:
- Week 35 and older: None reported locked.
- Week 36-38 inclusive: A scattered few reported locked.
- Week 39-44 inclusive: Most CPUs reported locked, the chance of being
locked increasing rapidly as the weeks progress.
- Week 45 and older: No CPUs reported unlocked.
The die locks affect the L3 (desktop multiplier) and L2 (L2 cache size) bridges
only. All other bridges remain modifiable.
In order to regain multiplier control, the CPU needs to be turned into a Mobile
CPU through the L5 bridge. The multiplier can then be changed through software,
though no current BIOSes support setting the software multiplier on boot.
See also:
Set to Mobile CPU
Mobile CPUs cannot do SMP