N900 performs like a dog if I power it up with the charger connected?
 

All

It seems to be a recurring thing i've noticed: if the battery goes dead, I connect the charger, wait a while then power up the phone and it runs like a turd; everything is laggy, delayed, keypresses are missed etc

If I remove the charger, cycle the power and then reconnect the charger when the phone has finished starting up, it's fine. What can I do to investigate why it is so bad?

cheers