K8N Neo 2 Platinum -- Hanging during boot --RESOLVED--

Question

Heres the problem...
My system will hang during boot at anytime, from bios initalization to full windows boot (No BSOD ever and where the pc hangs in the boot proccess is totally random). And the only way to get past the hang is do a soft reset. I have to restart my system up to 3 times before I get a good boot, but once the pc is up and running, it stay running till I shut it down. (no hangs)
Now if I shut it down after the system has been running for a while, the pc will restart normally without any hangs. The hangs only occur after the pc has been down for a time.
I have reseated all the connectors, the memory (even tried different slots), add-in cards, cpu.
I have a clean install of Windows XP Pro (hard drives have been repartitioned and reformatted as NTFS)
All fans are spinning up fine, all temps are within norm, power supply voltages are within norm.
No phsysical signs of bad caps on the system board.
I ran ran Memtest86 for 18 hours striaght with no errors.
Ran CPU stress test with no problems.
No IRQ,DMA,etc conflicts found.
Windows records no errors during a freeze and I have checked for unwanted services/proccess as well.
I have tried min install to no avail.
Bois is retaining its settings (so bios battery is good)
I do not over clock anything. Bios is set to discover all important setting automaticly. (Bios setting are the same now as they were 6 months ago)
I am down to a possible cold solder joint on the system board?
This problem started to occur about a month ago.
If someone has seen this exact problem and has a resolution, well I would appreciate it if you passed along your knowladge 
I am down to my last option of RMAing my system board. No. I have not replaced any components due to the fact I don't have extras lieing around nor can I spend the money just to troubleshoot :(
Specs..
Athlon 64 3500+
2 gig (pqi TURBO 1GB 184-Pin DDR SDRAM DDR 400 (PC 3200) Unbuffered System Memory Model PQI3200-1024SB)  Ran in Dual config
Geforce 6800  (BFG 6800 GT oc)
Creative X-Fi XtremeMusic
Antec NeoPower 480
2 WD 36gig SATA Raptors in raid 0 (system partition)
2 WD 120gig IDE  in raid 0 (data partition)
Windows XP Pro
all drivers and bios are manufacture ref and up-to-date.
Ok I won't go into all the details of why I missed this but it turns out the northbridge heatsink fan had stopped spinning and thus the hangs during boot due to overheating (hhmmm, when I step back and look at this the symptoms point right to overheating).
This also expains why after several attempts at booting up, once the pc was up it would run like a champ. The chip would of course overheat and cause random freezes. Now due to the placement of the chip and the design of the heatsink once there was enough airflow over the heatsink the chip would remain cool enough to prevent further freezing of the system.
What helped to facilitate this is that I have a ducted fan system installed in the bottom of my case which directs a substantal amount of fresh air to the pci slots, the chip set and the AGI slot as well.
So what have we learned class?
1. check the obvious
2. do a complete physical inspection of your system
3. KISS  -- keep it simple stupid

Answer 1

Is this your ram:
Quote
Part Number: PQI3200-1024SB
Quality Control: Comprehensively and rigorously tested
Package: 1024MB single pack
Organization: 128M x 64-bit
CAS Latency: 3-4-4-8
Test Voltage: 2.6 V
PCB Board: 8 Layers PCB
Heat Spreader: Mirrored Black Copper
Speed: DDR 400 MHz (PC3200)
Type: 184-pin DDR SDRAM
Error Checking: Non-ECC
Registered/Unbuffered: Unbuffered
Warranty: Lifetime
This is a quote from MSI web site:
Quote
Main Memory
  • Supports dual channel DDR 266/333/400, using four 184-pin DDR DIMMs.
• Supports the memory size up to 4GB 
• Supports 2.5v DDR SDRAM DIMM 
Due to the High Performance Memory design, motherboards or system configurations may or may not operate smoothly at the JEDEC (Joint Electron Device Engineering Council) standard settings (BIOS Default on the motherboard) such as DDR voltage, memory speeds and memory timing. Please confirm and adjust your memory setting in the BIOS accordingly for better system stability.
Example: Kingston HyperX DDR500 PC4000 operates at 2.65V, 3-4-4-8, CL=3.
For more information about specification of high performance memory modules, please check with your Memory Manufactures for more details.
Manually adjust your ram voltage to 2.65 volts and then manually adjust your ram timings to 3-4-4-8-2T.
If that does not work then do as Richard suggested and strip down to a bar-bone system, this is CPU+fan, 1 stick of ram (try other stick and different slots as one may be bad), graphic card and PS-2 keyboard, if it boots fine without any problems then add one device at a time until you find the problem.
Post back results as there are more things one can try but lets start with the simple stuff and work up.