Skyrim keeps crashing to desktop. Help please?

Have had Skyrim on PS3 since launch but found myself wanting to experience all the fun and goodness of the modding scene. So out I go and get myself a nice new updated PC to really show me how Skyrim is meant to be played. Well, so far, not so good... It keeps crashing to the desktop (steam screen) and when I pull up task manager it shows that it is unresponsive. As this is my first foray back into PC gaming in quite some time, I have no idea what the go is. Naturally, I have the HD Texture pack DLC downloaded but thats all so far, in terms of mods. Seems to happen at random times, too. Sometimes 10 minutes or so, other times an hour or more of gameplay, but it always seems to end the same: CTD.

 :cry:

My PC specs are as follows:

Operating System
    MS Windows 7 Ultimate 64-bit SP1
CPU
    AMD FX-6100 Six-Core Processor @ 3.32GHz
RAM
    16.0 GB Dual-Channel DDR3 (9-9-9-24)
Motherboard
    Gigabyte Technology Co., Ltd. GA-990FXA-UD3 (Socket M2)    41 °C
Graphics
    E2251 (1920x1080@60Hz)
    AMD Radeon HD 7900 Series
Hard Drives
    117GB Corsair Force GT ATA Device (SATA)    30 °C
    977GB Seagate ST31000524AS ATA Device (SATA)    34 °C

Any suggestions as to what the problem may be would be greatly appreciated.

Wow... This board is certainly very helpful. -.-