[I.M.O.G.]

Here's how to do CPUz on Bulldozer. Anyone out there with Bulldozer and LN2, hopefully this will be helpful. Worked pretty good for me. I do this with intent to kill something, but if you somehow don't kill anything doing this, please don't blame me that everything survived. I learned this from PhenomII experience, one FX-6100 is the only Bulldozer CPU I've tried out so far, and I observed also while Chew* and Macci were at AMD in Austin breaking the world record earlier this year.

This is easy, but this post is a bit long because I have spelled out very specifically what to do, but it is not complicated. I made sections so you could skip to what you are looking for. Ask if you have any questions. Keep in mind everything below was done at -190C/-374F at the base of my cooler. If you attempt this on air or water cooling, please post including pictures and video.

Table of Contents
Preparation
BIOS Settings
Using PSCheck
Finding Max Frequency
Conclusion and Final Notes

Preparation:
1. Got PScheck
2. Bios that allows disabling on a per core basis, not only per module (for the Asus CVF, this meant bios 9913)

BIOS Settings:

1. In bios disable everything for power management, including throttling - when you load windows, you should start with a consistent CPU frequency in CPUz. If its fluctuating, go back to BIOS to disable the right stuff.

2. If you can disable on a per core basis, turn one core on in two different modules. You need one core per module so that you can change frequency of each core independently. On bulldozer, you cannot change frequency independently for cores within the same module. If you are overclocking both cores and not only one, you will have a harder time hitting higher frequencies.

Using PSCheck:

Get it here. There are some instructions in that thread also, but they are a bit disjointed. PSCheck allows you to set multipliers on a per core basis - this is important as you will be running 2 cores for CPUz, one core will be idling at a safe frequency, the other will be maxed out for CPUz validation. For this example, we will be overclocking core 0, and this is how to use PSCheck:

1. In pscheck, go to File>Settings and select the PState Configuration tab. Place a check next to "all" in the left side panel to select all cores. On the right side panel, deselect the enable checkbox for Pstate Pb0 and Pstate Pb1. Then select the Boost Configuration tab and place a check next to "cpbdis" (disable cpb) near the top. Finally, click Save CPUs and Exit. This ensures you get consistent frequencies from your PScheck settings, without any throttling or jumping around to cause instability.

2. Go back to File>Settings and select the Pstate Configuration tab. In the left hand pane, click on core 0 to select it. On the right hand panel in the "Pstate P0" row, select your desired multiplier setting under CPUFID. To know what multiplier setting you want, look at the frequency column to the right after you choose a setting - the value in the frequency column divided by 200 is the multiplier that will be set. Once you have the multiplier you want, save cpus and exit. Ignore all other columns/settings. This saves the multiplier setting, but IT DOES NOT APPLY IT YET.

3. To apply the multiplier setting you selected, on the main PScheck window under "Processor Performance States" there should be two columns labeled 0 and 1, for each core you have enabled. In order for your multiplier to be applied, you must toggle the setting for core 0 from Pstate P0 to Pstate P1, then back to Pstate P0.

Finding Max Frequency:

1. Ensure CPU-NB does not limit you: Set CPU-NB in BIOS to a relatively low multiplier, as its frequency will increase when you raise FSB. Run generous volts. (I like to keep CPU-NB between 2600-4000MHz when FSB is increased, and I run 1.5-1.6V) Extra CPU-NB volts may help when more vCore does not, it helped me validate 7GHz on Phenom II.

2. Ensure HTLink does not limit you: Set HT Link in BIOS to a relatively low multiplier, as its frequency will increase when you raise FSB (I like to keep HT Link between 1800-2800MHz when FSB is increased)

3. Ensure RAM does not limit you: Set RAM multiplier as low as possible (I used 1066), loosen timings, run generous volts.

4. Max CPU Multiplier: Set vcore to 1.8V, set CPU-NB to 1.5V, then Set CPU Multi to the maximum setting it can do. (On my board with the FX-6100 that multiplier was 31.5) This meant I started out at 6300MHz.

5. Max FSB: Start at a frequency of 7000/multiplier (7000/31.5 = ~220MHz). Increase FSB in increments of 5Mhz, until it crashes - this is quicker if you have a good software tool, like TurboV or ROG Connect. Once it crashes, increase vcore by .05 or .1 (what you are comfortable with), then try to max FSB again, going in 1MHz increments once you get close to the frequency you crashed at before. Once you crash again, either increase vcore again or move on to the next step.

6. Reduce Multi by .5, Max FSB: Same as before, but your FSB will be higher this time. See if you improve your CPU frequency using this slightly lower multiplier.

7. Repeat step 6 as necessary. During the last few steps, tweak voltage settings as desired to get the last drop.

Conclusion and Final Notes:

That's how I got the highest CPU Frequency score on OC Forums. Now come and get me.

Notes:
-I went from 1.8V to 2.1V on vcore. From 1.9-2.1V was just making sure I couldn't get any more out of it on multis between 30-31.5. My highest frequency was 7744MHz at 1.872 vcore.
-I only maxed one core, the other core sat at a comfy/stable 5-6GHz. All other cores were disabled in BIOS.
-You may read elsewhere that PSCheck can kill your CPU if you use certain cores or modules or whatever. I don't believe thats true - I do believe that sometimes chips just randomly die when you are putting 1.8-2.2V through them. But PSCheck could have bugs that make sea-pea-uze asplode, dunno.

Brolloks mentioned I have the CPUz record on the team, so I figured that is my queue to write up a quick guide.

[mdcomp]

Great guide!

What would you suggest for a safe Vcore limit on water cooling or air cooling for those of us without LN2 at our disposal? I might pick up this platform to play with on DICE, so 1.8 might be pushing it there, too.

Matt

[I.M.O.G.]

Sort of feel like an Alcoholic advising someone about sobriety here, but I personally would be comfortable doing 1.55 to 1.6V on air/water cooling for max CPUz assuming its top-end air cooling.

There's a guy that did 6GHz on a single stage with the FX-6100 at 1.728V. That's probably pushing it, as I assume with a single stage he could probably do temps similar to DICE on one of these chips - depends on the quality of his phase changer really, but it's a guestimate. There's another guy with an FX-8150 that did 6.8GHz on dry ice at 1.75V too.

I probably wouldn't recommend running those voltages 24/7, unless I was comfortable with possibly having to replace my CPU. I don't know how long these chips stand up to voltage with prolonged use.

[bmwbaxter]

Thanks!

This is going to help a lot since I only have 1 AMD run under my belt. I wasn't too sure of all the NB/HT link settings. Hopefully this will allow me to get to at least 7500mhz. because in this day and age my 7276 is shameful

[I.M.O.G.]

We'll definitely get you to 7.5GHz Baxter, but our goal for you is now 7.8GHz.

If you run a stripped bench OS, you may first want to see if pscheck will install on it. If so, grab one of the attached BIOS files and we're ready to rock. 9913 is for cpu core on/off and some 3DM01 settings. Or grab 9920 which Shamino posted yesterday, but its the same as 9913 plus a cpu microcode update to fix a steam games issue (doesn't matter for our purposes).

You also need CPUz 1.58.7 to read your CPU correctly, which will also show CPU-NB frequency unlike version 1.58:
http://www.cpuid.com/news/47-cpuid_r...bulldozer.html

[PhIlLy ChEeSe]

Originally Posted by I.M.O.G.

Sort of feel like an Alcoholic advising someone about sobriety here

ROFL! I love it!

[Woomack]

Originally Posted by I.M.O.G.

1. Ensure CPU-NB does not limit you: Set CPU-NB in BIOS to a relatively low multiplier, as its frequency will increase when you raise FSB. Run generous volts. (I like to keep CPU-NB between 2600-4000MHz when FSB is increased, and I run 1.5-1.6V)

You said 2600-4000MHz CPU-NB like it's something easy on FX Really I'm curious, I wish to see memory performance @4GHz CPU-NB ...

Thanks for guide , my current mobo won't let me set anything higher but maybe one day I will try ...

[I.M.O.G.]

I actually haven't tried superpi yet - so I don't know much about a good cpu-nb on bulldozer. except 3800/4000 was easy peazy on my chip. when I tweak out superpi, I will getvto know what the cpunb can really do - makes a big difference for 32M.

[I.M.O.G.]

Updated title to 8GHz, reference: http://hwbot.org/submission/2222100_...20_8060.51_mhz

[hokiealumnus]

*cough* Put this on the front page. *cough*

[GoD_tattoo]

Loving the voltage....Nice Job!

[I.M.O.G.]

Originally Posted by hokiealumnus

*cough* Put this on the front page. *cough*

Done:
http://www.overclockers.com/howto-8-ghz-bulldozer/

[hokiealumnus]

Well done! (and Thanks!)

[capttripppp]

Your article made it over to the Bot! Go OCF Awesome article BTW Matt

[I.M.O.G.]

Cool, glad they posted it. Thanks for the heads up.

[bennoculus]

Thanks for this, Matt. This makes me want Bulldozer to go with my new dewars; then my Koolance-V2 would actually be excellent for it!