Easy as 1, 2, 3, Overclocking the A64, Optron, X2.

[Anonymous]

***bios descriptions are from the DFI Ultra-D and SLI-DR, yours may differ some but the principal will be the same***

!!!!! This is not a definitive guide to overclocking, it is MY quick and dirty way to get a fast overclock. This guide will not maximize your performance, it will only enhance it. If you want to find the maximum performance read some of the stickies that help you find the highest overclock for each of the 3 steps described below. As usual I and the owners of the forums take no responsibility if you damage your stuff. You break it you bought it. Use your brain when overclocking keep an eye on temperatures and don't use unreasonable voltages, you can damage your equipment if you don't. This guide is a living document I will update it as corrections are made and new techniques are adapted. Please do not post flames, keep it to constructive information or questions regarding this guide. !!!!!

1. Test the limits of your HyperTransport bus (HTT).

To do this set your CPU to its lowest multiplier. Generally 6x is good enough for this test.

Now set your memory to its lowest divider, 133 is general recommend.

Begin your testing by raising the FSB with the FSB/HTT multiplier set to 5x. Push your HTT up in 5mhz increments until it becomes unstable, generally you back off 5mhz from the last unstable speed. As Quailane pointed out its also a good idea to test with the 3x multi to ensure that your motherboard is not FSB limited, using the same steps test at both 5x for max HTT and 3x for max FSB. Testing should then be done, boot to windows and run a few loops of 3DMark03 or 05, if the system does not create any errors then you know its OK to move on to step 2. If it does fail out then reboot and back off the FSB another 5mhz, and retest.

Once your done note your max HTT number, a pad of paper is your friend so write it down if you think you might forget.

2. Test the limits of your memory.

This time around we are going to rest the FSB to 200 and set the FSB/HTT multiplier to 3x. Go into the memory section of the bios and set the memory speed to 200mhz (1:1) this means that for every MHz you increase the FSB you increase the speed of the memory. Again leave the CPU at 6x so it does not become the bottleneck.

While in the memory section of the bios you should set it to your preferred timings, I'm not going to go into detail on how to overclock your memory. I generally set most things to auto for this part of the testing other than the main four timings (Tcl, Trcd, Tras, Trp).

Again we start testing by incrementing the FSB by 5MHz at a time. You can safely start off at the rated speed of your memory and rated timings if you want (ie. PC3500 at 215fsb). Use Memtest86+ for testing, I generally use 5 passes of test #5 and 5 passes of test #8 for a quick test, this does not mean its stable but it does mean its probably safe to continue on. If you start getting errors in either test you can either lower your timings or increase your voltage. TCCD based memory does better when you loosen timings, BH5/UTT does better when you increase voltage.

Always keep an eye on the bandwidth in the upper left hand corner of the screen this tells you if you improving or hurting your performance with the timings you have set. If for example you can hit 240fsb with 2-2-2-6 or 250fsb with 2.5-3-3-8 you may find that 240fsb gives you more bandwidth and is there for more desirable, so pay attention to this value and WRITE IT DOWN along with your timings that way you can find the best performance.

When you think you have found the limits of your memory let Memtest86+ run through at least 10 full passes of all tests. Again this does not mean its stable only that its most likely good enough to move on to step 3.

3. How high can your CPU go. UPDATE for X2

This time around you want to set you CPU to its stock multiplier. Drop your memory back down to 133, and keep your FSB/HTT multiplier set to 3x. Reset your FSB to 200 and then your ready to test.

Using 5mhz increments start to increase your FSB. Test using SuperPi 32m, if it passes then repeat until it fails out, you can then either back off or give it some more voltage. When you feel you have achieved your maximum overclock on the CPU test for at least one hour with Prime 95 Torture Test set to small FFT. No this is not considered stable but your almost there :)
X2 Update
If your using this guide to overclock your X2 your going to do the same thing until you get to this point. Here things change a little. Your going to have to test each core independently.

To do this use the same principles as overclocking a single core but keep the second core under full load. Use a program that will not error out like S&M to do this and then stress test the core you are overclocking.

Then repeat this step stress testing the second core with S&M running on the first core to keep it at full load. This ensures that your CPU is always at full temperature so you don't get bogus overclock results on either core. After finding the limits of each core set both to the lowest maximum speed and stress test both using Prime95.

You will have to make two directories ( Prime95_1 and Prime95_2 ) for it to run, you will also need to set processor affinity, this option is under the Advanced menu. Like single core stress testing you should run this for 12-24hrs on BOTH cores with no errors. Now your done.

A little FYI keep your eyes on heat, when I was running my 4400+ I was seeing temperatures around 60c on the PWMIC as well as 60c on the CPU when running at 2.6ghz. Two core's means more power so if you have a cheap board keep your eye on the heat so you don't burn out your motherboard.

3DMark03
3DMark05
Memtest86+
SuperPi
Prime95
S&M

[Tyreal]

Thanks man. I have yet to try overclocking anything higher than an AXP so this was a good read for me. I will certainely be trying this out when I get my new rig.

Great guide man.

[sbohdan]

thanks a lot. this guide is very helpfull to all that have a double core AMD. maybe after years with intel I should give AMD a shot :)

[ccarroll321]

hi,

im using my A8R-MVP bios to clock my x2 3800. out of curiosity i tried out the pre-made overclocking profiles the board comes with. when set to 10% it clocks the CPU to 2200mhz, HTT 220mhz. the voltage stayed at 1.3 (according to CPUZ).
i get a small increase in framerate

when i set it to 15%, which sets the core ta 2300mhz, HTT 230mhz, the voltage still staying at 1.3 (according to the bios anyway); i get lower framerates then the regular factory 2000mhz.

for both cases, the clock multiplier was kept at 10x.
this does not make sense to me and im hoping someone can help.

thanks

[Tyreal]

It seems to me that the your CPU may not be receiving enough voltage. Try increasing the vcore up one one level higher.

[Miazga82]

Originally Posted by Tyreal

It seems to me that the your CPU may not be receiving enough voltage. Try increasing the vcore up one one level higher.

Exactly ... try to set it at 1.4V.

[Capper]

1.3V is way too low...I agree here. try 1.475-1.4V....that should bring the stability up

[gvblake22]

Originally Posted by ccarroll321

when i set it to 15%, which sets the core ta 2300mhz, HTT 230mhz, the voltage still staying at 1.3 (according to the bios anyway); i get lower framerates then the regular factory 2000mhz.

for both cases, the clock multiplier was kept at 10x.
this does not make sense to me and im hoping someone can help.

thanks

What is probably happening here is that it is running your RAM on a divider so when it increases the HTT speed, the operating frequency of your RAM stays at or under 200mhz. Another problem might be coming from your HT bus being out of spec depending on if the auto overclocking is lowering the LDT multiplier. Open CPU-Z again and click the memory tab and see what speed your memory is running at. If your memory is running slower than 200mhz, that might be the cause of your decreased performance.

Personally, I never bother with any "auto" overclocking features because I never know exactly what is happening with the system; I just prefer to be in control I guess. Try turning the auto-overclocking off and just change the clock speeds manually and see how it does. Remember that your RAM's speed will increase as the HTT frequency increases (if you have a 1:1 divider), you might either need to tweak the RAM timings or set a CPU:RAM divider to keep your RAM speeds in check. And don't forget to lower your LDT multiplier as the HTT speed increases so you don't push it past the 1000mhz bus speed (2000mhz effective).

[Tyreal]

Personally, I never bother with any "auto" overclocking features because I never know exactly what is happening with the system; I just prefer to be in control I guess. Try turning the auto-overclocking off and just change the clock speeds manually and see how it does. Remember that your RAM's speed will increase as the HTT frequency increases (if you have a 1:1 divider), you might either need to tweak the RAM timings or set a CPU:RAM divider to keep your RAM speeds in check. And don't forget to lower your LDT multiplier as the HTT speed increases so you don't push it past the 1000mhz bus speed (2000mhz effective).

Ditto. I never use the auto overclocking features either. It may be good if you just want to have a very slight overclock but if you are going for anyhting higher than do it manually. The New article on the front page by Thunda will help you overclock your CPU manually.
(LINK...)

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