Hi,
depp_x, and welcome to the forums.
I noticed you said you got *some* sound using the jack in the back - assuming the red is a light red, I beleive that is the line in jack - and thus the sound would be (naturally) low level as it is used for line in.
Now, are you using the front panel jacks? Another poster here went around and around in circles trying to figure out why he could not get the mic working- and it came down to a small setting in the RealTek drivers - disabling the Automatic jack detection on the front panel.
See if this helps you.