Published on May 2nd, 2011 | by Klaslo.com
AMD Phenom II X4 955 Black Edition Overclocking
AMD Phenom II X4 955 Black Edition (C3) runs at 3.2Ghz Stock and I have managed to overclock it to 3.8Ghz using stock voltage (1.4v) using stock heatsink and fan.
I overclocked it using AMD’s Overdrive application in Windows rather then is BIOS, this way I could see and test if the PC was stable.
The best settings for a stable system and temps I ended up with the following setting:
I just changed the Bus Speed to 238 while leaving the multiplier stock @ 16. This way you overclock the CPU and RAM at the same time, also I change Fan control to manual and set to 82% (any higher is better but for noise I left it at 82%)
With the Fan speed set to 82% (around 3000rpm) idle TEMPs @ 3.8Ghz are around 38C and at load are around 55C which is pretty good for stock heatsink and fan.
However please note that I am using ArticSilver 5 as the thermal paste.
Voltage issues while Overclocking
For some reason the motherboard kept on increasing the CPU voltage past its normal setting of 1.4V (for the C3 version, the C2 version the stock setting is 1.35V) when I left the CPU voltage control to AUTO. the motherboard increased the CPU voltage to 1.456v causing the CPU to heat up to 70C at load ! after many tries I ended up changing from Auto to Manual and then to Normal setting, because under manual 1.4v it would underclock the voltage to 1.34v making the system unstable. I believe that this is a issue with the motherboard BIOS and not the CPU.
Bechmark Results with Geekbench 2.1.12 for Windows x86 (32-bit)
CPU = AMD Phenom II X4 955 Black Edition C3
RAM = 4GB Corsair DDR2 800 5-5-5-18
Motherboard = Gigabyte GA-MA790GP-DS4H BIOS F6
Video = HIS HD6870 1GB 900/1050
PSU = Corsair 620HX
HDD = 2x500GB Seagate 7200RPM RAID 0
CASE = Antec 900
OS = Microsoft Windows 7 Enterprise x64