SHOULD be just fine.... might be some setting ....
can you tell me more about your set up ? which Macbook Pro ... Which model Sony TV .. what cables your using ... so on and so on ..
I hook up my Macbook Pro to my philips 52" all the time with no issue.. and my mac mini too ..( infact the tv IS the monitor for the mini ... tho I just remote into it most the time anyways .. it's my server)
The vid card in any MBP should be more then powerful enough to run a HDTV. but the more info the better I can walk ya thru the issue.