Hello everybody, my first post ;-)... (ah! and sorry for my english

)
I've been reading the forum for several days... and I can only say three things: thanks, thanks and thanks!

, reading this forum has helped me to overclock my system to my main goal: 4GHZ stable, although I would like to improve the voltages.
These are my settings for 4Ghz:
CPU MULT=20
BCLOCK=200
DRAM Freq=1600Mhz (x8)
UNCORE Freq=3200Mhz (x16)
QPI LINK SPEED=AUTO
CPU Voltage=1.3375
QPI/VTT Voltage=AUTO
DRAM Voltage=1.64 (8-8-8-24 fixed)
CPU PLL Voltage=AUTO
IOH Volateg=AUTO
ICH Voltage=AUTO
LOAD LINE CALIBRATION=LEVEL1 (In Gygabyte MOBO, there are four options: auto, standard, level1 and level2)
Intel HT Technology=Enabled
Intel Virtualization Tech=Disabled
Intel Turbo Mode=Disabled
All energetic functions (EIST...) Disabled
The core temps after one hour of prime95 are (aprox)
Core0=75
Core1=72
Core2=71
Core3=72
It is curious that core 0 always has 3-4ºc more than the others cores (is normal?)
well... with the QPI/VTT voltage in Auto, I don't know which is the voltage actually applied for QPI/VTT. In my MOBO, the QPI/VTT has these possible values: auto, normal, and numerical. With AUTO, I have passed IBT and prime95 for several hours. If I change it to 1.2 (normal), prime95 freeze (without BSOD) after one hour aprox...
Must I to go up with QPI/VTT voltage from 1.2 to achieve a stable system with minimal QPI/VTT voltage? ...
or the AUTO value is the best option?
Some advice to improve this configuration?
Thanks!!!!!!!!