I've been running stable for at least a year and a half with my 920 OCed to 3.5Ghz with 6GB of RAM.  Since RAM prices have dropped a bit I decided to double up. I Installed an additional 3 GB of matching RAM and immediately ran into problems.  First, on first boot Windows reported 12 GB installed (9.99 usable).   The 9.99 usable seemed really odd to me and I knew I had a problem.  Anyway, I then ran the Windows memory test.  I left it running, but when I cam back I had a BSD (0x07 stop as I recall).   So, I set my BIOS back to default settings, set the memory timings to the memory spec and ran several passes with MemTest.  The memory checks out at default settings.  I am running with default clocking for now.
 
What should I be looking at here?  My OC specs a listed below.
 
Mother Board ( EVGA X58 Classified 760 )
Drivers ( current )
Bios ( 80 )
CPU ( 920  DO)
CPU Cooler ( Cooler Master V8 )
Memory (6 GB Corsair XMS  PC12000 DDR3 1600MHz (8-8-8-24))
PSU ( Ultra X3 1000W )
GPU ( GTX 295 CO-OP x 1 )
Drivers ( 195.62 )
Operating System ( Windows 7 Ultimate 64-bit Release)


Frequency Control
CPU Clock Ratio ( 20X )
CPU Host Frequency (Mhz) ( 178 )
MCH Strap ( Auto )
CPU Uncore Frequency (Mhz) ( Auto)
CPU Clock Skew ( 0 ps )
Spread Spectrum ( Disabled )
PCIE Frequency (Mhz) ( 100 )
OC Recovery ( Disabled )

Memory Feature        
Memory Speed ( Standard )
Memory Control Setting ( Enabled )
Memory Frequency ( 2:8 )
Channel Interleave Setting ( 6 Way )
Rank Interleave Setting ( 4 Way )
Memory Low Gap ( Auto )
tCL Setting ( 8 )
tRCD Setting ( 8 )
tRP Setting ( 8 )
tRAS Setting ( 24 )
tRFC Setting ( 74 )
Command Rate ( 1T )


Voltage Control
EVGA VDroop Control ( With VDroop )
CPU VCore ( 1.26250 )
CPU VTT Voltage ( +100)
CPU PLL VCore ( Auto)
IOH PLL VCore ( Auto) 
QPI PLL VCore ( Auto)
DIMM Voltage ( 1.65 )
DIMM DQ Vref ( +0mV )

IOH VCore ( Auto )
IOH/ICH I/O Voltage ( Auto )
**BR04 ( NF200) Voltage ( Auto )
**VTT PWM Frequency ( 250 KHZ )
**CPU PWM Frequency ( 800 KHZ )
**CPU Impedance ( Auto )
**QPI Signal Compensation ( Auto )
ICH VCore ( Auto )


CPU Feature
Intel SpeedStep ( Disabled )
Turbo Mode Function ( Enabled )
CxE Function ( Disabled )
Execute Disable Bit ( Enabled )
Virtualization Technology ( Disabled )
Intel HT Technology ( Enabled )
Active Processor Cores ( All )
QPI Control Settings ( Enabled )
QPI Link Fast Mode ( Enabled )
QPI Frequency Selection ( 4.8 GT/s )


PnP/PCI     PCI Express
Maximum Payload Size ( 512 ) 

I really haven't tried anything else yet--hoping to get some guidance.  The VTT+100 has been like that the entire time.   How much would you think it show go up?
 
I need to be careful because I use this machine for work too.

I agree, try +150 and if that doesn't work try +200 (I don't remember if there is a +175 but if there is try that)

OK. This morning I tried VTT at +150, +175 and +200.  MemTest started getting errors during test 5 on the 1st pass (about 15 mins.) in every case.  Then, I set everything back to default clocks and ran a few memtest passed clean.  I rebooted then I started getting errors in Windows, the finally a BSD stip 0x3B.  
HalloweenWeed, how sure are you about the 2T and would the mem gap be causing this kind of thing?  I have just about decided to give on the 12 Gig.

Loose the timings a bit. run them at 9-9-9-24. and set these settings on your bios
 
CPU Uncore Frequency (Mhz) ( Auto)  x16
Execute Disable Bit ( Enabled )  Disabled
 
Post your results
 

BMoffa

Getting worse!  I pulled the new mem and put my old OC settings back in and this thing won't even POST.  Back to basics again.  What the heck is going on???

Previous OC settings won't work when you add new hardware.  You need to redo/reapply your OCing.  Start with the default settings and work your way up, just try to remember the settings you have on your previous OC.

BMoffa

Actually I didn't add new hardware.  I just removed the new mem and put my old OC settings back to where they were before the new mem.  That's when it doesn't POST now.  Those settings were good for at leat 18 months.

Adding more memory is considered hardware, even if it is 1 stick of memory. I upgraded memory and CPU. I tried using previous OCing settings to run my rig and I had the same issues as you.  I started from scratch, I reset the bios and little by little i got my OCing settings back.  I will recommend to do the same with new memory installed.

BMoffa

Shouldn't the 12 gig work with standard clocking though?  Or, do I need to adjust timings, etc. just for that???

Yes you do. It is basic computer setup routine. XMP spd tables were supposed to eliminate this need, but according to reports of users for the last three years EVGA boards do not do this well; so using "XMP memory profile" is not recommended, and even the manual clearly states not to use it if you OC your CPU.
 
Bottom line: ALWAYS enter your latencies and V manually. You should also set your mem multi manually.
Have you set 2t yet? Your mem is 2t.
 

Just for your info on this board please do not use the Corsair XMS profile. Set everything manually to include the DIMM voltage. I have Corsair vengeance LP which runs at a low 1.35 volts and it sees all of the ram at default levels.

Try these things:
DIMM 1.7V
tRCD (the second latency) 9
 

HalloweenWeed, Is that to get the mem running at 1600 or for the 178 Host freq. OC?  How high is too high on dimm voltage?
 
And, the mem. is the same stock no. and the same specs but purchased a year and a half apart (different lot numbers). 
 
Edited.........
Tried the 1.7 Dimm v. and timing.  With mem freq of 2:12 (1600) Host freq 133.  Windows reporeted 12 GB (5.99 usable).   Will try moving the memory around.   First, I will just put the new stuff in without the old and see if it will handle my old OC.  
 
It may take a day or two to get back.

I suggested those settings bc I had to set my mem at 1.7V to get it to run at full speed, but only when my CPU was near full OC. Besides that, OC status irrelevant, I had to set my 9-9-9-24 memory at 9-10-9-24 to get it to run at full 1600 without occasional BSOD about once a week. So I thought maybe if you did the same...
 
Now you should work on determining whether your prob is caused by CPU or mobo (or RAM). You would need to swap things out to do that. GL.

Any recommendation on a 12GB 3-Stick set of 1600GHz.  I probably will not try to push the CPU much beyond 3.55 (Host freq 178) because of cooling.

How about this? 
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231457

I don't have my heart set on anything but GSKILL was suggested above.  Will take any recommendations.  But remember I'm not going for much above 3.5 because of cooling.