Just rolled back the Driver for the processor update I applied last night and now all is well again
It now shows as 1.8Ghz even when removing the psu, I assume this processor update added AMD's equivelent to Intels Speedstep, wich would explain why everything was so slow.
Pitty really, it did make my battery last much longer (Nearly 3 1/4 hours) but it meant that I couldnt watch any Video, and browsing internet was painfully slugglish).