P6N Diamond and Wolfdale E8400 Decision

Question

I recently built a new machine with the Intel Wolfdale E8400 processor, 2 sticks of 2GB (5-5-5-18) OCZ Reaper DDR2800 RAM and the P6N Diamond motherboard. I thought that since the motherboard supported
Core 2 Duo and a 1333 MHz FSB that surely it must support the Wolfdale.
Silly me. Initially my system locked up and rebooted with artifacts whenever I tried to run 3D Mark 05. At first I blamed my new videocard, the MSI NX8800GT and RMA'd it. Since I got back the same card I sent, the problem must not have
been the graphics card.
Sure enough, it turned out that I hadn't plugged in 8 pin ATX12V connector! I thought that surely the 24 pin 12V connector would be enough, right? How the system even POST-ed on my first attempt I don't know. Once I fixed that, the system was able to run 3DMark 05 without locking up and rebooting. I then played Oblivion for about an hour with all the settings cranked up ( 1920 x 1200 x 32 w/ everything set to high but no AA ). 
Then I noticed that under 'System Properties', Windows only listed 2.5 GB of RAM when I had 4GB of RAM.   
I was aware of the 32-bit Windows XP RAM limitation and expected to see at least 3 GB.
I then found out that the latest BIOS 1.3 could fix the  problem.  After the BIOS update and loading the fail-safe defaults, I reran 3D Mark 05 and sure enough it hung and reboot (this time with no artifacts.)
I set Windows to not reboot on system error so I could actually see a BSOD if there was one, but the BSOD would flash on the screen too fast before the system rebooted. 
I then cleared the BIOS, re-loaded fail-safe defaults in BIOS, and reinstalled Windows.  Windows then reported 3.0 GB of RAM and the machine finally completed a run of 3D Mark 05 without locking up and rebooting.
I learned 2 lessons there:
1) Don't update your BIOS unless there's something REAAAALLY wrong
with your system and
2) If you do, make sure to clear your BIOS afterward.   
Then I decided to try Prime 95.  I selected 'Blended Tests' and a few seconds later the machine would again lock up and reboot. It was at this point that I decided to send the MSI support people a message.
My response was that the P6N Diamond does NOT support the Wolfdale E8400 processor.
Anandtech.com even says that it does!!!
A coworker of mine has his machine working with the EXACT SAME PROC AND MOBO!!!!! 
I tried underclocking the FSB to 1066 MHz, which reduced the proc to 2.4GHz and the DDR2-800 memory to 533MHz and Prime 95 ran overnight. 
Just when I was about to give up hope and try to sell the 'officially incompatible' P6N Diamond, I stumbled onto a forum thread involving the P6N Platinum.  Apparently, someone with a similar problem with the P6N Diamond
figured out that if he increased the voltages (CPU to +0.0250, Memory to 1.85 V, NB Voltage to 1.35, SB Voltage to 1.55 V and FSB VTT to 4%) then the system would be stable.
On a lark, I tried those settings and now the system is stable at 3.0 GHz and a 1333 MHz FSB and my DDR2-800 running at 667MHz.
Overall it seems as if I am having to overclock my system just to get it to run at STOCK speeds!!!!
 This doesn't seem right given that other overclockers are getting at least 3.6 GHz with their Wolfdales. 
Should I try the P7N Diamond?

Answer 1

Here are the PSU Specs:
Corsair TX750W Specifications:   Model CMPSU-750TX
AC INPUT
90-264V ~ 10A 50/60Hz
DC OUTPUT
+3.3V
+5V
+12V
-12V
+5Vsb
MAX LOAD
24A
28A
60A
0.8A
3A
MAX COMBINED WATTAGE
180W
720W
9.6W
15W
TOTAL POWER: 750W
I got that particular PSU because it has a dedicated single +12V rail. One of my co-workers had
a problem with a power supply with multiple rails and passed on a recommendation
that for the sake of simplicity, a PSU with a single rail was best. 
The PSUs with multiple rails seem to involve more care in plugging in components as far making sure that
the parts are getting the right amount of current(?)