The noob guide to overclocking A64 CPU's

PV5150

New member
So you’ve just bought a brand-spanking new 64-bit processor from AMD huh? To you my fellow PC user, I say; congratulations and of course, enjoy. We all know just how fast an AMD 64 is straight out of the box, it’s fast enough to chew through just about anything you throw at it, literally speaking. So why on earth would you need, or want, more processing speed from this already fast CPU? Well you might already know the answer to that, maybe you just want something more for nothing? For others however, it’s an addiction. Admit it, you are an overclocking addict. You can’t bare the thought of having any piece of hardware in your rig running at “stock” speed. The sound of it is almost offensive to your ears. Or perhaps you just love looking at bigger numbers; you love the feeling of knowing that your CPU is running 200 MHz faster then its original speed – and you grin deviously when you get that extra performance boost. You know the feeling, most of us do. Excuse the borrowed pics, but you'll get the idea and these pics will not be the same as your bios screen



Overclocking an AMD 64 is relatively simple. Just up the FSB and voltage and hope for the best, right? Wrong. While the main idea is to get that FSB nice and high, there are many other adjustments you must make in order to prevent your pretty CPU from turning into a blob of melted silicon. Before you even begin to dive into that blue-BIOS-of-hell, you must first understand some key points.

Note #HTT or Hyper-Transport Technology Is often mentioned in the BIOS as LTD speed.



It should have a multiplier setting next to the name, ranging from 1x to 5x. This multiplier relates to your FSB. So for example, 5 x 200 MHz FSB equals 1000mhz, still with me? Then that number is doubled to effectively give you the overall Hyper-Transport Speed of 2000 MHz. You should know that HTT speed is not the CPU Clock speed; it is simply a technology that deals with the memory controller featured on AMD 64’s that involves the amount of bandwidth available. However, you must note that having a slightly lower HTT speed will most likely not have any impact on gaming performance. So a 3x or 4x multiplier is just fine. The main idea is that you stay under the maximum HTT speed supported for your Motherboard’s chipset. Which brings me to my next point…

Command your RAM

Memory Command Rates can be awfully confusing at times. You should find an option somewhere in that BIOS of yours that mentions “Command Rate” somewhere. When you do, there will be two options; 1T and 2T.





Doesn’t sound complicated, but this can play quite a significant part in running a high FSB. The most important thing to remember is, a 1T command rate is much faster then the 2T, but (there’s always a but isn’t there?) in most occasions you will be able to push the speed of the RAM further with 2T. Running a 2T command rate will only ever be faster then 1T when the actual memory speed is much higher. For example, 1T @ 210 MHz is almost equivalent to 2T @ 240 MHz.

It is generally considered that if you are using 2 sticks of RAM with your A64, you should run the 2T command rate. However, A64’s can be found with different stepping revisions, which I won't go into at the moment as I shall confuse the hell out of you.

Tweaking Time

Last but not least, voltages and Latencies. What’s Latencies you ask? Excuse me while I gouge out my eyeballs before I answer that, but long story short: it involves how fast the RAM responds to commands. For a more in-depth explanation, Google is indeed your friend. So, obviously the lower the Latency times the faster the RAM should perform. Once again, another ‘but’, this time it’s to do with overclocking, what a coincidence eh? Most RAM will be able to clock higher when the latencies are more “relaxed”, as in slightly slower, which allows for more oc’ing headroom to stretch its legs.

Now voltages can be dangerous if used incorrectly, after all, the last thing you want is to end up with a fried chip. Increase the voltages, on either, up in tiny increments, only if you absolutely have to. You’ll know when you need more voltage if you 1) Are experienced or 2) Being told by an experienced person.



So there you have it, all the basic fundamentals you need to understand when you are playing, sorry “tweaking cautiously” around with your AMD 64 CPU. Remember, overclocking does require extreme patience, and it helps to know exactly where that CMOS battery, or jumper, is located on your motherboard. In case anything goes horribly wrong, or you simply are unable to even boot the computer, consult your motherboard manual to find out where the CMOS battery is. All you have to do is short the battery, wait a minute or so, and your default BIOS settings will be returned, how convenient.

Getting Started

When you first begin to raise that FSB, in 5MHZ increments at a time, keep in mind that if your RAM divider or ratio is set to 1:1, then your RAM will also increase its speed. You will also get better performance with running the FSB and RAM in sync, 1:1 ratio, so try to find your RAM’s limit before you change the divider to something like 5:4. Also remember what your chipset’s maximum HTT speed is in MHz , then once you have gone above it, you should lower the HTT multiplier.

If your overclock is successful and you can boot into Windows, first run a program such as Prime 95, or any other CPU intensive benchmark, to see if you still maintain adequate stability. Then, once you’ve found the highest, stable clock, try running SuperPI . This will give you a sign as to whether all your hard work payed off.

PV
 
Good job PV.

Mod reps for you :worship::worship::worship::worship::worship::worship:

If u like, i can take some screenies of certain areas of my bios, so you dont have several different makes of BIOS in there ;)
 
name='PV5150' said:
Thanks Jim, that offer would be very much appreciated. It was correct though wasn't it, just for clarifcation?

Yep. Looks good.

I assumed that as this was a n00b's guide, you didnt want to confuse the matter by including things such as increasing voltages etc?
 
Yeah might be good to get some of the DFI BIOS in there...its confusing....especially finding the command rate command!!

PV - your guide making is legendary. This will help out loads of n00bs out ther. I salute you sir!! :worship: :worship: :worship: :worship: :worship: :worship:
 
Yeah thanks XMS, I just wanted to get a start for ocing A64's so incorporating voltage adjustment would just confuse newbies. XMS do you wanna put in the screenshots for me pls?

Thanks kempez, the screen shots are all over the shop but that was all I could find lol. Thank you for the compliment :o :o
 
FINALYY I GET IT so its all about finding the "GOLDEN SPOT" in all of the components :worship: :worship: nice job PV :worship: :worship: thanks alot for the help !!!!!!

if by any chance my comp doesnt boot wat do i do with the cmos battery??
 
{TAS}Lone Shadow Wolf said:
FINALYY I GET IT so its all about finding the "GOLDEN SPOT" in all of the components :worship: :worship: nice job PV :worship: :worship: thanks alot for the help !!!!!!

if by any chance my comp doesnt boot wat do i do with the cmos battery??

If you take a look at you motherboard manual there will be shown the CMOS jumper. You simply power down completely (IE pull power cable out and wait 10seconds after switching off), then switch the jumper over to the "reset" position for 30seconds. switch it back and you have a reset CMOS.

You shouldn't need to do this when OC'ing as you BIOS shouls always load up ok. I have used it for other stuff a few times tho :o
 
Yeah it is mate...al about the 'sweet spot', and you are most welcome-hope it helps!!! In the event you can't get into Windows, just turn the computer off and reset the jumper. By this I mean move the jumper from it's current position and move to the reset position, leave it there for about 10 secs and then move it back again to the original position- consult your manual for this.
 
kempez815 said:
If you take a look at you motherboard manual there will be shown the CMOS jumper. You simply power down completely (IE pull power cable out and wait 10seconds after switching off), then switch the jumper over to the "reset" position for 30seconds. switch it back and you have a reset CMOS.

You shouldn't need to do this when OC'ing as you BIOS shouls always load up ok. I have used it for other stuff a few times tho :o

Also, as you have got an Abit motherboard, you can reset your BIOS to fail-safe settings by holding down the 'Insert' key when starting your machine ;)
 
name='{TAS}Lone Shadow Wolf' said:
so basically tht is the only thing that can go wrong :rolleyes:

At this level of overclocking, yes.

There is very little risk involved with small overclocks. Its when you get to water/phase cooling that things get risky ;)
 
{TAS}Lone Shadow Wolf said:
ok kool i so need better cooling but ill wait till i upgrade my system

so if i oc right will there be good increase in the performance of my machine ????

Depending on how far you overclock, will depend on how much of a increase you get.

But i'd say that most people with reasonable hardware are at least guaranteed a 200mhz overclock - which certainly isn't to be sniffed at.
 
{TAS}Lone Shadow Wolf said:
so kepp LTD speed under 5x

set DRam @ 2t

increase FSB in 5mhz increments

if go above HTT speed Lower multiplier

is tht it? :o :o :p

You are best setting the LTD multi to 4x - that will mean you'll be good to overclock your FSB (ht) up to 250 without any problems - but remember to still only go up in increments of 5mhz
 
Back
Top