Really simple question about recording inputs

[Mercutio]

Im trying to record from both Mic and Line-in at the same time. This appears to be failing somewhat - anyone know whats needed or how to go about it?

 

[Hen_Dawg]

Some sound card may not work this way. What do you have?

 

[Mercutio]

Its fairly basic cheesy onboard. Im not using anything amazing recording wise, simply something I wanted to record using sound recorder for a friend. The recording options give a tick box for which input to use but wont allow multiple.

Im likely in the market for a card this month. Would the usual sorts like the x-fi etc give me more joy or would I need something a bit more "serious". The inputs are only mono so im probably going to head to a high street electrical kit store, find a stereo splitter and simply use line-in for both. It's not something I need to do often but would be nice to know its do-able with the usual cards.