I'm trying to overclock an AMD Phenom II X4 940 CPU. I'm using a Scythe Mugen II Rev. B CPU cooler. I have a Biostar T-Series motherboard and I'm OC'ing from the bios.

The reason I'm overclocking is to run the Pcsx2 emulator at full speed, I plan to change back to stock speeds when I'm not running the emulator.

This is my first time overclocking and after doing some reading I decided to only mess with the multiplier and CPU Core voltage. I managed to get a stable clock at 3.6 Ghz w/ x18 mult. and upped the stock voltage from 1.35v to 1.45v. Idle temps are 30c while full load temps are 40c. Games are much faster than they were at stock but I still need more power to run at full speed.

Now i'm stuck at a wall trying to reach 3.7 Ghz. I tried raising voltages to 1.5v (the max in the spec for my cpu) and would still crash after one minute of running Prime 95. I did some reading online on how OC'ing the Northbridge would help stabilize my overclock and raised it from the default 1600 Mhz to 2000-2400Mhz. When that failed I tried raising chipset voltage (northbridge voltage) from default 1.20v to 1.40v. Still no luck.

Any advice on how I can reach 3.7 Ghz would be appreciated.

Today I underclocked my CPU back to 3.0Ghz and overclocked my northbridge from default 1600 to 2000Mhz (stable without touching chipset voltage) and my performance in PCSX2 was actually better than it was on 3.6 Ghz. What exactly does the Northbridge do again?

Increasing NB basically increases meory bandwidth, so as you increase your cpu frequency, increasing NB helps the cpu talk to memory so both together will show a marked improvement. Ht is more video related and appears to have less of an effect. The problem with increasing Frequency without increasing NB is that your cpu end up being limited by memory bandwidth, Sp clock you cpu back to 3600 and leave your Nb where you found it to be stable and it will good. Also increasing volts can sometimes actually decrease frequency, read about it, was having issued with my NB so dropped the NBv and it became stable. So sometimes it is better to drop volts to get it stable.

-------------------------
Gigabyte Ga8800 ga UD3
AMD 1090t @ 4.14 GHz(1.45V) NB @ 2800
Nvidia 560ti gtx 1Gig
8 Gig Corsair 1600 Mhz DDR3
Win 7 64 bit Ultimate