t40 monitor freezing problems

[maxlev]

my t40 monitor randomly darkens, freezing up. sometimes if i close and reopen or gently shake the machine it comes back up, but frequently it is just frozen. sometimes this freezing happens when i move the machine slightly and other times it just blanks out with out reason. i have tried reinstaling drivers and software issues, but it seems not to help. there is also a general noisieness to the machine as of late and infrequent discolorations on the screen. any advice? something loose inside, and if so what?
thanks