Overclocking (a Quick How To)

[leezard]

*****Overclocking VOIDS your warranty, it can also cause damage to the components of your PC, If you try to overclock your computer and it dies in a cloud of smoke, myself or TCH cant be held responsible. Overclock at your OWN risk *****

 

That being said, heres a quick how to on overclocking, It is by no means a complete run through but more of a refrence guide. I didnt write this guide, but it does a decent job of explaining hows and whys.

 

CPU.

There are 2 ways to overclock your CPU........upping your multiplier or upping your FSB. Uping your multi only affects your CPU, upping your FSB will affect your CPU, RAM and possibly your PCI and AGP cards (if ur mobo doesnt have a PCI/AGP bus lock like the NF2 chipset gives u). Upping your FSB is preferably as it will give you greater bandwith and higher benchmarks. But before we get to that lets discuss burning in. Burning in is one of those questionable things ; Some people swear that it helps, while others say its useless. The purpose of burning is is that its supposed to get you better overclocks later on. The steps are :

1. Drop your Multi and FSB so you have a really low speed (like 10x and 100 FSB giving you 1000MHz).

2. Raise your Vcore to as high as your willing. Absolute max on air (and mabye water) is about 1.9V, but id suggest 1.8-1.85V.

3. Run a burnin program, such as Prime95 for 24 hours. Id suggest monitering temps for the first few hours (esp if ur using 1.9V). If temps top 55C kill ur power, and lower the voltage by .5V.

 

Next thing to do i test how high you can raise your FSB. To do this lower your multi to as low as you can (bout 5x), raise your voltage to 1.8-1.9V (you should have figured out how high is safe during burning in). Then start raising your FSB. eg. if ur original FSB is 133 then raise it to 160. Run p95 for bout 12 hours......if it has problems then your FSB is to high. (NOTE: for those of you using the Nforce 2 chipset now is the time to activate the PCI/AGP bus lock. Those of you running the KT400 chipset note the divider is 5. Therefore ur PCI/AGP bus is FSB/5. If your PCI/AGP FSB goes over 40 then your HD may corrupt (38 is the highest id go). Thus you shouldnt put your CPU FSB over 200 (id keep it at 185-190)). Keep raising your FSB till it wont go any higher.........this cap is most likely caused by your RAM.

 

Lastly, with your FSB as high as it will go, raise your multi till you have your desired speed. eg. my desired speed is ~2400MHZ (a 400MHZ overclock). Therefore my desirable settings are Vcore = 1.85V, FSB = 185, Multi = 13 (cause 13x185=2405MHz). Ive chosen 185 FSB because im running a KT400 motherboard (so my PCI/AGP bus is at 185/5=37), and my RAM is going to be running at 370MHz (FSBx2=370, thus CPU and RAM are in sync).

 

RAM.

With DDR there are also 2 ways to increase speed. Both require that you increase you Vdimm for the best overclocks. Note: try not to get your Vdimm over 2.8V (i think 2.5V is default setting).

1. You can increase the speed of your RAM eg. If your running PC2700 (333MHz) DDR you can overclock to 350MHZ.

2. the second way to speed up RAM is to tighten the timings. To explain timings im goin 2 rip from VIA's website (http://www.viaarena.com/?PageID=101) : go there to see what it all means. Basically your RAM has a set of timings eg. 3-3-3-8-2t. By lowering these numbers (eg. to 2-2-2-6-1t)in your BIOS (know as tightening the settings) you get the RAM working faster. The most important of these numbers is the CAS latency setting, hence high end RAM such as cosair will be advertised as 'gaurenteed CAS 2'

 

Better quality RAM= better overclocks.

 

if you want a more comprehensive overclocking guide heres a good one.

 

http://www.anandtech.com/showdoc.html?i=157

Edited May 30, 2003 by leezard