So i want to buy a 5.1 sound system for my pc, but a friend of mine ( who has one ) said my pc needs atleast 5 connections..... i have five but im not sure if they are the right ones:
yellow/orange one
blue one
black one
pink one ( i know that this one is microphone :3 )
grey one
green one
i hope that these are all i need...
oh yeah, pls suggest me a cheap but good 5.1 system cause i dont have much money too spend atm.

I wouldn't recommend geting one for your room, I would rather get a headset, like the Logetech G35 (7.1 USB). The green one is the front left and right speakers, The orange one is the center speaker/sub-woofer and the black one is rear surround and the audio out connector. I hope I could help. -Graboy

yeah thy nao i know what the connections are for
i dislike headsets pretty much cause i love to hear music on speakers just to feel the vibrations of the bass in some techno songs of mine

The amount of connections you need depends on the speakers & your sound hardware. The last surround rig I used was a single TOSLINK rather than 1 cable per channel. Regardless it got ditched for a 2.1 set simply because having speakers all over the place was annoying. >_>