I installed ubuntu 12.10 in an eeepc 904ha. It worked fine untill i removed the hdd and plugged it into an acer aspire one laptop. the touchpad gets disabled on boot on that laptop, but it has a key to enable it. When i plug the hard disk back into the 904ha, it wont work after login. It works on the login screen, but no further. xinput list gives :

⎡ Virtual core pointer                    	id=2	[master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer              	id=4	[slave  pointer  (2)]
⎣ Virtual core keyboard                   	id=3	[master keyboard (2)]
    ↳ Virtual core XTEST keyboard             	id=5	[slave  keyboard (3)]
    ↳ Power Button                            	id=6	[slave  keyboard (3)]
    ↳ Video Bus                               	id=7	[slave  keyboard (3)]
    ↳ Power Button                            	id=8	[slave  keyboard (3)]
    ↳ Sleep Button                            	id=9	[slave  keyboard (3)]
    ↳ CNF7129                                 	id=10	[slave  keyboard (3)]
    ↳ Asus EeePC extra buttons                	id=11	[slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard            	id=12	[slave  keyboard (3)]
The touchpad is missing from xinput. My keyboard isn't exactly in mint condition and i hate having to use it for navigating menus. Please help me out coz i just spent $200 (probably twice it's worth now) on getting it back into working condition and a full re-install is overkill