P55 LE with I5 750 OC'd to 4.0 ghz (200BCLK X 20) will not boot with 4 sticks o

[Macgyver321]

Hello denizens of overclockers.com!

I've often lurked here and now I must come to you for help. After getting excellent advice from the folks over at www.overclock.net, I have narrowed my problem down to RAM.

I have got a solid overclock with my I5 750 at 4.0 GHZ, however, when I have more than 2 sticks of RAM in my system, the computer will constantly reboot before it even gets to BIOS.

I have ruled out the RAM sticks or slots being bad because if I do not overclock the CPU at all, all 4 2-GB sticks of RAM work just fine. Another thing to note is that all 8 GB of ram are the exact same brand and model (Corsair XMS). Lastly, I recently had all of this working fine, even with 4 sticks of RAM, however, I unfortunately had to reset CMOS for an unrelated reason and did not remember exactly how I had my Freq/Mem settings. Shame on me!

So, what do you guys think? Here are some specs from BIOS to help with the diagnosis:

DRAM frequency: 2:8 (1600mhz)
Timings: 9-9-9-24
CAS: (9)

MCH Strap: 1600MHZ
Vcore: 1.35
DIMM Voltage: 1.65
CPU VTT: 1.25
PCH: 1.050
CPU PLL: 1.8

Now, keep in mind, this works great with my 2 sticks of DDR3. The problem arises when I put the other 2 stick of 2GB each into the system. After I do that the system does not post and goes into an infinite loop. I've tried upping the VTT to 1.35 and even 1.4 to no effect. I've also tried uping the PLL to 1.9 and the PCH to 1.125, also, no help.

Thank you all in advance!

 

[redduc900]

Fill out this BIOS template for the P55 w/ all of your current settings using 4GB of RAM...

*Frequency/Voltage Control*
Dummy O.C :
Target CPU Frequency :
Target Memory Frequency :
CPU Multiplier Setting :
CPU Frequency Setting :
PCIE Frequency Setting :
QPI Frequency Selection :
MCH Strap :
Extreme Cooling :
EVGA VDroop Control :
Current CPU Vcore :
Bootup CPU Vcore :
Eventual CPU Vcore :
Current Dimm Voltage :
DIMM Voltage :
Current VTT :
Bootup CPU VTT :
Eventual CPU VTT :
Current PCH Voltage :
PCH :
Current CPU PLL :
CPU PLL :
DIMM 1/2 DQ Vref :
DIMM 3/4 DQ Vref :
DIMM 1/2 CA Vref :
DIMM 3/4 CA Vref :
CPU PWM Frequency :
VTT PWM Frequency :
DDR PWM Frequency :
CPU Signal 1 :
CPU Signal 3 :
CPU Signal 4 :
CPU PCIE 1 :
CPU PCIE 2 :
DDR Signal 1 :
DDR Signal 2 :
DDR Signal 3 :
DMI Signal :
PCH Signal :

*Memory Configure*
IMC Type :
DRAM SPD :
DRAM Frequency :
Target Memory Frequency :
DRAM tCL :
DRAM tRCD :
DRAM tRP :
DRAM tRAS :
DRAM tRFC :
DRAM tRRD :
DRAM tFAW :
DRAM tRTP :
DRAM tWR :
DRAM tWTR :
Command Rate :
CHA Round Trip Latency :
CHB Round Trip Latency :
Memory Low Gap :
Memory Remap Feature :
PCI MMIO Allocation : 4GB To 256MB
Memory Hole :
DRAM Margin Ranks :

*CPU Configuration*
Configure advance CPU setting
Module Version :  
Manufacturer :
Intel (R) Core (TM) :
Frequency :
BCLK Speed :
Cache L1 :
Cache L2 :
Cache L3 :
Ratio Status :
Ratio Actual Value :
Hardware Prefetcher :
Adjacent Cache Line Prefetch :
MPS and ACPI MADT ordering :
Max CPUID Value Limit :
Intel (R) Virtualization Tech :
Execute-Disable Bit Capabili :
Intel (R) HT Technology :
Active Processor Cores :
A20M :
C1E Support :
Intel (R) SpeedStep (tm)  tech :
Intel (R) C-STATE  tech :

 

[Macgyver321]

Well, it's hard to believe but I actually got the system to boot with all 4 sticks. How I did it I still do not understand.

Knowing it was unhealthy and possibly hardware damaging, I raised the Voltages to much higher specifications than would be recommended for even 1 hour, much less 24 / 7. I raised Vcore to about 4.0, DIMM to about 1.9, VTT to about 1.45, PCH to 1.125 and PLL to 1.9.

I reboot with just 2 sticks to see if it would even turn on and it did.

I decided to throw in the other 2 sticks, bringing the total to 4, and hit power button. To my amazement, it worked.

Before getting into Windows 7 I jumped into Bios again to make sure all of the RAM was reporting. It was. I then decided that if this is going to be an actual solution, I need to step down some of these Voltages and narrow down the problem. I started with Vcore, continued to DIMM and ended at PLL.

To my shock, the computer booted after all voltages were returned to what is listed above.

WHAT?!

I'm not sure exactly why that is, I can hypothesize, but really it's going to take some research to figure out what happened.

My recommendation to anyone else having this issue (and specifically this issue, be warned that raising your voltage settings too far can damage your components) is to first follow all of the other advice you get from Overclocking guides, and when all else fails raise up your voltages past where you are comfortable, and slowly tick down to find out what is stable.