currently i have a computer that can do up to doby 7.1 and im using speakers to do 5.1 but recently they have been fading in and out... they are 5 years old so im not surprised.

i want to replace them and i have 4 very nice Cambridge Soundworks speakers but they are for a home audio system.

so my question is and there some sort of amp that i can buy to use them for my computer or do i have to but a full out receiver? or are there any other suggestions?