Well the missing pin might become a issue in certain cases, but if its booting and running it looks like you are safe. So far thats 800MHz, as said before is just Cool'N'Quiet down clocking for lower temps and power usage.
I would keep an eye on it though. Any weird behavior or crashes could result in something worse.
ok what i tryed doing is running Crysis, and immediately it jumped to 3200mhz. so i guess its all good. thanx for your help everyone. and i must be crazy lucky because it turns out i have 2! broken pins. not just 1