AMD Athlon 64 X2 7750 2.7 GHz Black Edition
Gigabyte GA-MA78GM-S2H (Rev2.x BIOS FC)
Western Digital Caviar Blue 640GB 16MB 7200RPM
Transcend aXeRam DDR2-800
Generic-ish Case & PSU
Installed a fresh copy of Win7 on the new HDD. Everything works without a hitch but when I try the sound nothing works. I've tried installing the drivers under different compatibility modes likes under Vista, XP etc but still nothing, the following is probably my 3rd format and install of Win7

take1: New install again. Plugged in my Z-2300s to the LR (green) port, any other working speakers I could find to all the available ports. No sound on first start up, no sound when playing Mp3. Also nothing detected by the mic.
I can see this pic in the sound settings with default win7 drivers. It says the speakers aren't plugged in but they are!

take2: Uninstalled the default drivers that came with Win7, and installed the Win7 realtek HD audio drivers... the Realtek HD Audio Manager icon shows up but when I open up the program none of the ports which are occupied are detected (ie still faded) and still no sound anywhere.

So throw me any tips, ideas or suggestions. I'm on the verge of giving up.
NB: I've tried to install WinXP after the format to rule out an OS problem but keep getting BSOD during the install, so a no go there at the moment (but surely changing the compatibility modes is sufficient??).