audiophile 2496 soundcard isn't getting input from microphone

[Lunahorum]

I have this cheesy microphone I bought from radioshack and it works fine with the realtek microphone input, but it isn't getting any input signal at all when I plug it into the 2496 soundcard. I don't have a preamp (I don't have enough money and I resort to using a noise filter in audacity), but I can play my guitar hooked directly into computer just fine. I am not getting any signal with the microphone hooked in though. I have also tried hooking the microphone into my amp, but still nothing. It only works when I plug it into my realtek motherboard sound card input. The funny thing is that my guitar also works when plugged into the realtek motherboard input.

That was badly worded so overall here's the question:

Without a preamp, I can play my guitar into the soundcard input and receive a signal no problem. I cannot hum into the microphone into the soundcard input and receive a signal. For some reason, the motherboard sound card "realtek AC97" can have a microphone plugged into it and do just fine. Now this is the standard $5 headset microphone from radioshack, nothing fancy. Just wondering why it gets a signal through the ac97 and not the audiophile 2496 (and yes I switched inputs in control panel - sound and audio settings because I can play the guitar just fine through both)

edit

even shorter version: if I can play the guitar straight into the soundcard, why can't I play the microphone straight into it?

On another note, what exactly does a preamp do? Without one, I am reading around -18dB on the guitar input (The soundcard goes down to -48dB). Would the preamp make it read closer to 0 or do something else? Thanks

[Veq]

I do not have a sollution, but just wanted to chip in. I have exacly the same problem with this soundcard. It can record my guitar, but nothing happens with my mic.

And just like you, it works in my Realtek soundcard on the motherboard.

I wonder if this is a common problem with this soundcard, and I would love to know a sollution.

[Skrypnyk]

perhaps it's because these input operate on a line-in, and not a mic-in?

[dannthr]

Did you try the difference between plugging your guitar and your mic into both the mic input on the Realtek and the line input on the Realtek?

I simply assume that your mic needs too much juice.

A preamp can do a lot of things, one of which would be to send more juice to your mic, but I wouldn't buy a pre for a $5 mic, it's not worth it.

[Lunahorum]

yea maybe that is it. I will try plugging the guitar into the mic in sometime.