[G4] Dual 1.25Ghz Fw800 showing up as 1GhzDP question

[Rod]

Hi All! 

But of a puzzle this one.  I have a Dual 1.25GhzDP (FW 800 model), which has
all the hallmarks that it is a 1.25Ghz DP - Radeon 9000, 80Gb HD, Airport
Extreme, Bluetooth module spot, FireWire 800 port.  The ethernet sticker on
the back states that it is a 1.25DP, and a search on Apple's serial check
also says its a 1.25DP.

When I go into Apple System Profiler and About This Mac, they both
state its a 1Ghz DP.  Also running the latest TechTool Pro 4, it also
states that the processor is a Dual 1Ghz. I have also run command line tools
which also point to a 1Ghz DP rather than 1.25Ghz.

Anybody else come across this?  The guy who I bought it from has had the PM
since brand new, and said then that the processor always showed 1Ghz DP (and
sold it as a 1Ghz DP), but as far as Apple is concerned the machine is a
1.25 (which may have a serious effect on warranty if the processor board
needs changing).  He is very trustworthy, so I am sure that he has not
changed the board, and he doesn't think it has been in for service.

I have tried resetting Open Firmware and PMU reset.

Any ideas? 

Seeya 

Rod!