if i were to get one of them..where would i find a fan to go with it?
whart are the chances of having a MXM Card in my pc working ?
That is a question I don't have an answer to. I think the AIO will be like a laptop with copper heatpipe conducting the GPU to the main fan, but since you don't have GPU installed already, I don't know if you have the heatpipe.
would this work?
nVIDIA GeForce GT 240M GT240M 1GB MXM VGA Graphics Card
In theory, it should work is you use the right drive.
Sorry, I only had MXM on laptop before, not AIO, so there is a degree of uncertainty and can only tell you so much.