During my testing to identify the issue I took the following steps.
1) Updated to the most current version of NForce drivers (requires several restarts)
2) After finding no joy with driver updates I pulled all personal information off of the drive
3) I reformatted the drive during a fresh windows 7 x64 ultimate installation
4) Using the stock windows drivers issue was still experienced
5) Ran windows update a bunch of times including all published WHQL drivers - issue still expereinced
6) reran most current nForce drivers. - issue still experienced
I have two issues I need to resolve
1) Intel SSD has SMART errors that need factory reset / repair
2) Dell XPS 630i has crappy bios drivers for NForce 650 SLI chipset.
http://support.dell.com/support/edocs/systems/xps630i/en/OM/HTML/specs.htm
my issue is not unique (quick google search has lots of hits with issues): http://www.my630i.com/viewtopic.php?f=6&t=3499