My studio is based around the following system.
A Gigabyte P67A-UD5-B3 with a Intel Core i7 2600K running at 3.4 Ghz. 8GB of RAM and twin ASUS 5450 graphics cards with a total of three monitors attached. Two used for a widescreen view of Sonar, the other for use over my main keyboard rack.
Multiple SSDs and HDs take care of storage with separate drives for OS, Progams, Audio data, and Samples.
All of that is housed in a Fractal Design "Define R3" case for "silent" running.
My interface is an Allen & Heath QU-24, that comes with onboard compressors, EQ, and FX. Occasionally the onboard compression is 'printed' but the FX and processors are manily for monitoring purposes. All processing is usually "In the Box" and applied post tracking. Main output from the QU-24 monitored via a pair of Behringer Truth B2031A monitors, with a couple of mixes fed to a headphone amp, and a wireless mointoring system.
DAW control surfaces are an MCU & XT.
I can also go mobile with a HP Elitebook 8760w running an Intel Core i7-2670M @ 2.20 Ghz with 12GB RAM and dual SSD & hard drive using a Roland Tri-capture interface for simple stereo capture.
The QU-24 ia capable of recording multiple channels to a USB drive if I need to perform multi channel recording.