Calling all old school AMD OC guru's, skt 939 x2 4200+ first time OC'er

[Ticker305]

Building a dedicated Diablo 3 gaming rig with a skt 939 Motherboard and AMD x2 4200+. I've never OC anything before and don't want to royally screw this up with a typical noobie mistake. I'm not trying to achive any world records or anything, just maybe get it from 2.2 possibly to 2.5mhz or whatever can run it stable.

I'm sitting right on the lower threshold of the Diablo 3 minimum cpu requirements (x2 4400+). So I'm trying to get it closer to the recommended standard (5600+ 2.8 GHz)

MSI K8N Neo4 MS-7125 Rev. 2.0
x2 4200+ (oem box stock sink/fan)
3gb ddr 400
hd 7750
cx 430 psu

Any help or a point in the right direction would be immensely appreciated, thanks.

 

[EarthDog]

I'm not an AMD guy.. but WELCOME! And check out the link in my signature for AMD overclocking until someone better suited can help.

But its basically raising the HTT/FSB up while keeping the memory under control.

 

[rescuetoaster]

Ok, so, I know nothing about that board, but I do know about overclocking the socket 939 X2 CPUs.

So, the motherboard uses the FSB value to calculate the Hypertransport (HTT) speed, the RAM speed, and the CPU speed. I had the 3800+ X2, so it had a multiplier of 10, and I'm guessing that your 4200 has a multiplier of 11 (FSB 200 X 11 = 2200 mhz). The HTT should have a multiplier at 5X at stock (FSB 200 X 5 = 1000 mhz).
So, first thing you should do is read up on overclocking just so you know what to expect and to get you comfortable with it.

Now, on to the meat and potatoes.

Since you will be increasing the FSB value to overclock your CPU, you need to make sure you do your math regarding the HTT and RAM speeds. Let's say you wanted to take your CPU to 2.75 ghz - you would set your FSB to 250, but since that will affect everything else, you need to drop your HTT multiplier to 4X which would still give you a HTT speed of 1000 mhz (FSB 250 X4 = 1000mhz) and you will (almost certainly) need to drop your ram speed to 133 (133 + 50mhz = 183mhz or 366 mhz effective).

Now, I did the 2.75 ghz number just for a demonstration of how the FSB will affect your other bus speeds. You do not want to overclock the HTT - it will become unstable VERY fast, and doesn't net you any performance gains on the 939 system. The RAM speed is also something you will have to play with - my Kingston Hyper-X that I had refused to overclock more than 5 mhz, so it made more sense for me to run my ram at a slightly slower speed so that I could run my CPU at a faster speed. Make sure you don't jump straight to 250 FSB, although that CPU would probably do just fine at 2.75 ghz (my 3800+ ran at 2.5, and a lot of people were hitting 2.8 on air).

Here is a good guide for you - I realized that I'm rambling. Read this.
http://icrontic.com/article/overclocking_on_754939_platform

 

[Ticker305]

Thanks for the warm welcome and the great info. The board just shipped this morning and should arrive here anytime early next week, until then will read as much as I can about basic OC. This gives me a much better understanding on how this socket operates and a good foundation to start with, thanks!