Settings for 3.8GHz overclock: i7-920, Gigabyte EX58-UD5 with latest F12 BIOS

I have updated my BIOS from f9 to f12 and have the below settings to overclock using standard TT template. Overclocking is more stable with these settings. The overclock is stable judge by running prime95 from 3 hours and 2 hour running memtest the CPU temperature is 40C.
Advanced CPU Features:
CPU Clock Ratio : 19
Intel(R) Turbo Boost Tech : Disable
CPU Multi Threading :Enable
CPU Enhanced Halt (C1E) : Disable
C3/C6/C7 State Support : Disable
CPU Thermal Monitor :Enable
CPU EIST Function :. Disable

Uncore & QPI Features:
QPI Link Speed :x36 7.2GHz
Uncore Frequency :x17 3400MHz
Isonchronous Frequency :Enable

Standard Clock Control:
Base Clock (BCLK) Control :Enable
BCLK Frequency (MHz) :200
PCI Express Frequency (MHz) : 100


Advanced Clock Control:
CPU Clock Drive :800
PCI Express Clock Drive :900
CPU Clock Skew : 0
IOH Clock Skew : 0

Advanced DRAM Features:
Performance Enhance : Standard
Extreme Memory Profile (X.M.P) : Disable
System Memory Multiplier (SPD) : 8
tRCD :8
tRP :8
tRAS :24
CR:2



Advanced Voltage Control:
Load Line Calibration : Standard
CPU Vcore .:1.275
QPI/VTT Voltage 1.150v :1.295
CPU PLL 1.800v :1.80
PCIE 1.500v :AUTO
QPI PLL 1.100v :AUTO
IOH Core 1.100v :AUTO

DRAM
DRAM Voltage 1.500v :1.64
DRAM Termination 0.750v: AUTO
Ch-A Data VRef. 0.750v :AUTO
Ch-B Data VRef. 0.750v :AUTO
Ch-C Data VRef. 0.750v :AUTO
Computer specification:
CPU: Intel Core i7 920
BIOS: F12
Motherboard: Gigabyte EX58-UD5 v1.0
RAM: 6G (3x 2GB) DDR3 memory 7-8-7-20-2T at 1.65V

I use settings given above for overclocking and achieve only 3.8GHz but it is unstable. The difference between your system and my system is memory I have 12Gb of RAM 8-8-8-24. Do I need to tweak it in order to make it stable? Thank you in advance for your reply.

Post back your current setting that are not stable so that we can help you with it. When you are saying that those setting are not stable, Did you get BSOD fail prime95 after x hours. As you have mentioned you have 12GB of RAM so this will require more QPI and VTT voltage. If you get BSOD error then check below which voltage to change:
BSOD error codes
1. 0x00000050 Incorrect memory timing/freq
2. 0x00000124 incorrect qpi/vtt voltage
3. 0x00000101 not enough Vcore voltage
4. 0x00000109 Not enough memory voltage

I use the below setting and get 3.8GHz
Advanced CPU Features:
CPU Clock Ratio : 21x
Intel(R) Turbo Boost Tech : Disable if you have 930 chip otherwise enable
CPU Multi Threading :Enable
CPU Cores Enabled :All
CPU Enhanced Halt (C1E) : Disable
C3/C6/C7 State Support : enable
CPU Thermal Monitor :Enable
CPU EIST Function :enable

Uncore & QPI Features:
QPI Link Speed :x36 GHz
Uncore Frequency :x17 MHz
Isonchronous Frequency :Enable

Standard Clock Control:
Base Clock (BCLK) Control :Enable
BCLK Frequency (MHz) :180
PCI Express Frequency (MHz) : 100


Advanced Clock Control:
CPU Clock Drive :800
PCI Express Clock Drive :900
CPU Clock Skew : 0 ps
IOH Clock Skew : 0 ps

Advanced DRAM Features:
Performance Enhance : Standard
Extreme Memory Profile (X.M.P) : Disable
System Memory Multiplier (SPD) : 8
tRCD :8
tRP :8
tRAS :24
CR:2



Advanced Voltage Control:
Load Line Calibration : Disable
CPU Vcore .:1.275
QPI/VTT Voltage: 1.150v [1.295]
CPU PLL: 1.800v
PCIE 1.500v :AUTO
QPI PLL 1.100v :AUTO
IOH Core 1.100v :AUTO

DRAM
DRAM Voltage 1.500v :1.64
All rest AUTO

I use these setting and system was unstable. Then I reset the BIOS to default an dagaing applied the same setting now seems to be more stable. Tried for an hour with prime95. But I want to achieve 4.0GHz or 4.2 GHz. I am having i7 and do water cooling with Corsair H50. 12GB RAM Corsair 8-8-8-24, one PCI Express video card. Please tell me what is the safest way to go 4.2Ghz without frying the chip?

I tried with your templates but I was unable to manage to be stable with 4.0GHz. Then I found some different setting on web and my 930 was 20 linx passes and 24 hours prime95 stable:
Cpu Ratio: 19x
Turbo: Off
Blk: 190
Dram Freq: 1531
UCLK: 3063 Mhz
QPI Link: 6893MT/s
Ram Timming: 8,8,8,24,1n
Load Line Cal: Auto
Vcore: 1.225(Bios) 1.230
CPU PLL: 1.800
QPI/DRAM: 1.3
DRAM BUS: 1.602
IOH: 1.16
ICH: 1.0
Power saving OFF
CPU Hyperthreading ON

thanks for the settings! :) I used it with my ex58-ud3r motherboard with a corsair h50 cooling and seems to be running pretty stable.. I have 12gb ram installed with specs of 12GB 3x4gb, 240-pin DIMM, DDR3 PC3-10600,DDR3 PC3-10600 • CL=9 • Unbuffered • NON-ECC • DDR3-1333 • 1.5V • 512Meg x 64 •
and was asking if i needed to tweek any of the settings?

and help would be appreciated

simon