According to Samsung's web-site, that set has a PC audio in (using 3.5mm jack) which would be the normal direct connection from PC to the TV though it might not work without the D-sub or DVI video connection - this would give you video effects from the PC player.
The RCA audio input might work for the AV composite input, though this might not be detected without a video input.
Another alternative would be to use the DLNA facility, if the TV is connected to your network; or else just connect a LAN cable between the PC and TV and set manual network addresses.
Hi - I want to connect my Acer Laptop to my Samsung UA40C5000 only to listen to music. I went to a shop, spoke to 2 different guys who both had completely different solutions and they sold me a Belkin RCA (RCA I think) Mini Stereo cable to connect the laptop up. I put the RCA end into the headphone socket of the laptop and into the PC input hole on the TV - nothing happened. Is this the wrong cable??? I just want to listen to music that I have sitting on the laptop. Help please.

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