Acer Aspire 4710 - Core 2 Duo — audio +screen

hi, first of all i am bit curious and wonder how can posting a complaint on this forum help!!!
any way i am an optimist, just hope for the best,
ok then, i purchased an acer laptop nov-2007.initially there was problem with the screen, the screen would turn blank white intermittently which i used to solve by pressing the sleep button(fn+ f4).there was no other problem then.
now recently i installed win xps2, (previously had vista).and my audio is totally dumb.when i tried to fix it going to devise manager i only succeded in getting an error message statting unable to start the device(real tec hd audio) i am unable to install audio driver, !!!
i can see a windows logo similar to an update logon in front my audio device in devise manager, so thought some updates may be the cause . thus deleted all the updates 93, you know thats a hard work..
but even then my audio didn't work.
at the day end i was disappointed an decided to have a treat and saw hancock on the web, yes with out audio!!!
any one who had got a satisfactory solution after siting yoour complaint here