As far as I'm aware, this laptop has a quad core AMD processor (which are not particularly good when compared to Intel equivalents), not an AMD 'drive'.
I'm not sure it's possible to replace an AB9 Lite processsor. Your best option might be to replace the laptop, or take it for repair. Not sure of how cost effective a repair might be, or if it's actually possible.
Am guessing OS in Win 8/8.1, so as a first step, have you tried running a check for viruses, malware, or system restore back to factory settings, at all?