New Build, Random Freezes and Restarts

Hey all, just looking for some help in diagnosing a problem with my new build. It has been randomly freezing during relatively light tasks (pandora, chrome, digsby, nothing major). The screen will lock, sound stutter and nothing will respond. I also just experienced the computer restarting randomly.

Anyway, here is the old build I had with NO freezes:
580w Hiper Power supply
2 9800gts in SLI
AMD Athlon 6000+
4 HD Raid (Windows Partition on this drive)
Auzentech xplosion sound card
8 gigs mushkin ram
M2n32 Sli Deluxe mobo

My comp was pretty old and basically reaching end of life so I added a few new parts to help ease the pain before I buy a new rig:
AMD Phenom 925
64 gig Samsung SSD (new Windows Partition)
various new fans/ cables/ case lighting
(I also added that second 9800 GT, but because it was a cheap ebay purchase I made sure it worked in my old build first)

During the rebuild I took everything apart, added several new case fans, painted the inside of the case, added case lighting, and heavily reworked my cable management... needless to say it took some time and I hope I can get everything up to speed again!

I just did a fresh install of Windows 7 yesterday. During the install I had a problem where the install would hang indefinitely at the "starting windows" screen. After removing parts one at a time, I found the culprit to be one stick of memory, which I removed.

My guess is one of these things is the current offender:
PSU is under powered
SSD is faulty
another Ram stick is bad (I just removed the ram stick that was paired with the first bad stick, will update if freezing continues)

Any advice, suggestions, help greatly appreciated

BTW, I have checked temps on everything and they seem good:
SSD is at about 27-28C (this is good? I don't even know really)
CPU is idling at about 30C
GPUs are idling around 55-60C (they ran real hot in my old build too, so I don't think that's the problem)

UPDATE:

After trying two clean windows installs, I took out the SSD and put in my old HD that used to have my windows partition on it.

This seemed to solve the problem...

Until it locked up again. That being said, it seems to be locking up much less frequently (only twice so far)

Could this be a problem with the SATA controller? Or maybe the port the drives are plugged into?

Again, any help would be greatly appreciated.

New updates:

I just ran memtest86 on all my RAM... including the one that I pulled at the beginning of the build to install windows. All sticks come out clean one at a time, but if I put all 4 in at the same time windows won't start and memtest freezes... and yet 3 sticks work fine, and it doesn't matter which 3 sticks.

Is this a power issue? A voltage/ timing issue?