GrobSMG 0 Newbie Poster

Hey all,
If anyone could help or give me an idea of what's wrong, that would be great... I purchased a new system and pieced it together:
AMD Sempron 3100+ (2.0GHz), 256Kb L2 cache
ATI All in Wonder Raedon 9600 128MB DDR AGP 8X
Gigabyte GA-K8NS,
1 GB DDR SDRAM (2 x 512 DIMMs)
Maxtor DiamondMax SATA 200GB Hard Drive (16Mb cache)
New case (ATX Power supply included)

Initially I popped in the WinXP CD, and after a couple of tries got to the option of formatting the drive (couple of times stalled while trying to examine the drive), and formatted fully. Then, it went to installation, but had errors, saying files would not copy correctly, and would you like to retry. So I had to retry quite a few files, but didn't say it couldn't copy after... So that went alright, but to get into the rest of the installation in windows, i had to restart a few times, because the WinXP screen would show up, but the blue bar would just keep scrolling with no results... when I entered the installation, it said files were not copied correctly...
So I placed DIMMs to different slots.
Afterwards, still took a couple of tries to get into the formatting, but I quick formatted and the dos-based installation worked like a charm... still when I went to reboot however, same thing happened with WinXP screen... when i managed to get into windows after a few tries, it finished the installation as it should, and then asked to restart... Instead of restarting, all i got was a black screen, no winxp logo showing or anything (after bios stuff). SO, after POWERING DOWN, it managed to restart and get into windows... great! It was working... So then I popped in my motherboard CD to update drivers, and it installed something initially, and restarting, SAME thing happened with the black screen, and would ONLY restart when i POWERED DOWN... but it restarted... i got back in windows, finished installation of whatever was left... and restarted.. but NOW, it just got stuck in a cyclical loop of rebooting (winxp screen shows up though)...

SO... I did a FULL reformat, and reinstallation, same things happened with the black screen, but now i didn't restart the 2nd time after installing the rest of the motherboard CD stuff, which now enabled me to use the internet, install graphic card drivers, etc... I was able to surf the net, install programs, etc, with no problems... ONLY when i went to restart, what happened? Cyclical rebooting again...

Last night, reformatted, same steps, same results, only I installed the motherboard stuff, and went to the website and upgraded to the latest version of that, and the audio motherboard driver... as soon as I got that audio one on, it messed up on me again and cyclic reboots... apparently that messes things up?... But still, with the improper windows rebooting, I'm not sure what's wrong....

Someone please help! Thanks!