best soundcard with amp and speaker.

Hi, Im just setting up a Hifi in my room through my computer. Well heres the story so far. I have an old Amp which is pretty amazing and soom good quality technics speakers(2). I hooked it up with a cable from the onboard card into the AUX and then through the speakers. To be honest it's not really doing the speakers and amp justice. It's just doesnt give the clarity of a normal Hifi. So my question is what it the best soundcard to buy? I have seen the creative audioligy 2 zs for £40 of ebuyer and really thats the most i want to pay. Would this give a great improvement in sound? Any help would be appreaciated as always, Thanks,John.

Could it be a preamp or impedance problem? I take it you are using onboard mobo sound, before you buy see if you can borrow a friends sound card. Is it set to stereo or 5.1 etc?

its not a problem just quality isn't as great as it could be. I have used the amp on other hifis and it works fine.Yeah onboard realteck 97 or something like that.

It seems the most likely cause is the onboard sound.

yeah I think your right. What about the soundcard, any recommendations?

m-audio revolution or something like that

where could iget one of them. The soundcards i have seen are on e-buyer and they are basically only soundblasters and audioligys.