Trying to Diagnose an Explorer Problem

I'm building a PC for a friend and will post the specs below. The issue is, on a clean install, the PC boots fine and loads to the desktop. Within the first minute of the PC booting, the HDD light goes on solid, and it seems that Windows Explorer hangs. I can still move the mouse cursor around, but I can't click on anything. If I let it sit for a minute or two, it seems to be fine. I have all drivers updated, and absolutely no software installed. I did install MSE and run a scan, but that came up clean (the problem existed before and after install). All Windows Updates are applied, and the problem existing before and after them. I'm not sure what else I should be doing to diagnose this.

AMD FX4100 proc
Gigabyte 78LMT-S2P
4 GB MicroCenter brand memory
WD 2500KS HDD
ATI Radeon 4350

I can't get task manager to open...that triggers the hang. Msconfig's start up tab is completely empty. I thought I had MSE installed, but I don't. I scanned the drive with the MSE offline disc, and found nothing.

Yep, I did so with the AMD chipset drivers, audio drivers, and network card. Once I installed those, I ran Windows Update, and the video drivers for the PCI-E 4350 were downloaded. I have no uninstalled drivers, according to Device Manager.

I got it from Gigabyte. Should I follow my own usual advice, and get it from the source? I normally build Intel only, so I always get my chipset drivers right from them.

Have you tried booting in Safe Mode?

I'm in the process of removing the chipset driver and then I'll install the newer ones from AMD. So far, in Safe Mode, it seems to be running ok.