Windows 7: Sony LCD & Dell XPS HDMI connectivity problem

dear frnds,

i m having a sony LCD TV KLV-26S550A as well as a dell xps laptop with this config :
17.3" screen
windows 7 Ultimate
Nvidia GT435 Card with 1 GB ram
4 GB 1333 MHz RAM


when i m trying to connect the HDMI o/p of lappi to sony TV, TV says unsupported signal. when i connected same cord with desktop, the LCD runs fine:means HDMI cable is fine. now when i connected my lappi to samsung LCD using same HDMI port & cabel it run fine.



so whts the problem in connecting dell lappi to sony only. as all other sets are working fine.

any remedy to apply.

bye

Unsupported signal is usually tv code for 'I don't know this resolution' have you tried changing the resolution before hooking it up?

yep,

i tried starting with 800x600 & gradually increasing the resolution but of no use. along with this when i tries the same lappi & cable on samsung 32", it worked fine.

bye