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Overclocking Tool for the Mac Pro

Digitalclips said:
You missed my point though, others are getting way higher and while I might use ZDNet Clock or not, currently I am more concerned that it might be showing up a bad RAM configuration I was unaware of, in which case I am really happy I tried it.
Click to expand...

Just cause the RAM can't be OC'ed doesn't make it bad. That was my point. As long as the RAM runs at the rated speed and you don't get errors in everyday use the RAM is fine. If it runs faster than the rated speed then great.

If you want to test your memory you are better off running Prime95 or SuperPI (to like 32 million).

If you take the Apple RAM out does it still OC poorly? Moving RAM around (to make it closer to the controller) is a good idea. Although I couldn't tell you what slots to use (FB-DIMMs are more picky about that stuff than normal DIMMs).

If the DIMMs still don't clock as well as you would like you may have to add voltage (which you can't do on the MP currently) as that is a common problem with lower quality DIMMs, they just need more juice to run faster. Apple most likely uses DIMMs that have more headroom available. Although I am sure Apple doesn't test FB-DIMMs for OC-ability (why would they). So even with Apple RAM you may not get golden sample material.
 
Christoph,

thanks for this great tool. Currently I'm able to get up to 3.15 from 2.8. and actually with the restart can get into xp64 with that speed, which is great.
the CPU temps are fine, and could actually go higher, but the memory temps are about as high as I feel comfortable pushing them.

I'm not a programmer, but I wonder if you would be able to use something similar to rEFIt. to get the buss speed up before the os loads? if it would work that would solve some issues. It wouldn't matter what os you wanted to go in, and if it could save the settings, then you wouldn't have to set it up after each restart. Ideally there would be a 10 second wait to let you go in and change things incase you needed to.

http://refit.sourceforge.net/

Thanks

Chris

p.s. You're not Christoph Pfisterer are you?
 
Well then, by the looks of it, the PC to MAC users out weigh the old school MAC fan boys (as we used to call them) and rightfully so.

I remember when the G4 laptop was touted as a PORTABLE studio and thinking, this machine is horrible, NO FPU what so ever (FPU is much needed for plug-ins), then of course was the over priced DUAL G5, and had to admit the OS when it got to tiger was sweet, OS9 was not, it was clunky, but still the DUAL G5 was trounced at the time, especially price to performance, with a AMD or INTEL chip.

Thank goodness for intel though, that being said, we really should be pushing for AMD to make something killer - as INTEL is back to its releasing CPU's very slow, yet when AMD was giving them a run for their money, INTEL was slashing the prices left and right and we won.

Still, while the prices have come down to some degree and a MACBOOK trounces a DUAL G5 for audio use (almost 100% faster in some areas), Apple still screws with the pro's and will say it again.

• No Bios, no overclocking the FSB, maybe this will change with ZDNET and you can thank them as Apple underclocks a lot of their GPU's and CPU's on the laptop for battery life, expect bettery battery with newer chips (when is this)

• ECC memory with heat sinks, not sure you can just buy ECC memory for cheaper and use it w/o Apples heat sink, a way for apple to get you to buy their memory, they could have used regular memory, which some has a high FSB, to be fair, it will run a bit more stable (like CPU's, memory also comes from the same silicon, is tested to see the threshold and labeled accordingly).

• No GPU on Mini, Macbook and custom gpu needed for all Mac Pro's -

• Firewire is problematic on macbook and iMac especially in audio work, some video, but mostly audio.

• Glossy screen on iMac means no color correction - not sure if it can be calibrated.

So, perhaps we should be happy for things like jailbreak as this might have launched the SDK, thank God for OSX86, as you can build a system right up there with Mac Pro for less. Thank goodness for INTEL as you can buy the cheaper CPU and overclock or just swap out the CPU for newer.

Personally, am waiting for the next gen MAC PRO as I think this machine, especially if in the same price range could see 3.2 as the bottom of the line and maybe 16 cores. Now we're talking TOY STORY RENDERING FARM.

Watch the video's on apple regarding FINAL CUT, one movie done all on ONE MAC PRO....would like to see 4 cores in a laptop, or even 8.:apple:
 
ts1973 said:
Instant freeze here on my Mac Pro dual 2.8, and I barely moved to 405FSb to get started.

Probably ram related : got 4x2 gb OWC and 2x 1Gb original Apple Ram...
Click to expand...

I experience (almost) the same.
Using 4x2 GB OWC RAM and 2x1 GB AppleRAM.

Getting Kernel Panic error...

G
 
I can't read that language. does anyone have the exact download link?

hey guys,

dos anyone have a link to the exact download, because I cannot read the language. It would be very helpful and greatly appreciated.
Thanks,
Mike

MacRumors said:


ZDNet.de has posted a new tool called ZDNet Clock Tool 1.0 for Mac Pro which allows you to overclock your Mac Pro. The process of overclocking uses software to increase your computer's processor speed and bus speed, potentially leading to higher performance. Boost the speed too high, however, and the computer may crash as either the processor or some of their components are unable to keep up. Still, ZDNet.de claims to have achieved some impressive results:The multi-page article (be sure to click on 'weiter' for next page) describes their results including stability tests over 24 hours. There are a few caveats as well:The application is available for free download from ZDNet.de (click on "Jetzt herunterlade" to download). Some MacRumors readers have already had some experience with this tool, but readers should proceed with caution.


Article Link
Click to expand...
 
seemseemo said:
hey guys, dos anyone have a link to the exact download, because I cannot read the language. It would be very helpful and greatly appreciated.
Click to expand...

The article tells you what to look for: The application is available for free download from ZDNet.de (click on "Jetzt herunterlade" to download).
 
hiimamac said:
• ECC memory with heat sinks, not sure you can just buy ECC memory for cheaper and use it w/o Apples heat sink, a way for apple to get you to buy their memory, they could have used regular memory, which some has a high FSB, to be fair, it will run a bit more stable (like CPU's, memory also comes from the same silicon, is tested to see the threshold and labeled accordingly).

• No GPU on Mini, Macbook and custom gpu needed for all Mac Pro's -

• Firewire is problematic on macbook and iMac especially in audio work, some video, but mostly audio.

• Glossy screen on iMac means no color correction - not sure if it can be calibrated.
Click to expand...

MacPro uses FB-DIMM which is a crazy volcano RAM type. It generates a lot of heat. That's not Apple's fault, it's Intel. We must blame Intel for their wrong selection, again!! (every body remember the RAMBUS?) So, for me the Apple requirement about heatsink for RAM is good!.

Mac mini, MB, iMac are not designed to be gaming machine or pro workstation.

(but anyway I hope Apple adds some top notch features to the Mac like before. I remember the Ti-book age, when you could work with it for 5-hour even on OS X....)
 
Digitalclips said:
Ok, help me out here ... sorry to be DIMM ;)
This Mac Pro is the first Mac I have seen wher the RAM is installed this way.

On A DIMM Riser is both Apple RAM DIMMs in DIMM slots 1 & 2.
On B DIMM Riser is both 3rd Party RAM DIMMs in slots 1 & 2 also

Where are you suggesting I move what to...? Do you mean switch 3rd party positions in slots 1 & 2 or move to 3 & 4 or are you suggesting switching Risers?
Click to expand...

I _think_ slots 1 in both risers are closer to the processor, and slots 2 are further away. On the other hand, slots 2 always take one cycle more for access, so they might have more spare nanoseconds. We don't know that for sure. And you said you can overclock further with Apple RAM only then with both sets of RAM.

I'd say put the third party RAM into slots 2 on both risers. If you can overclock further, excellent. If things get worse, also good, because then you swap both slots 1 with both slots 2 and things should improve.
 
The memory is what is going to limit your clocks, well that and the lack of voltage control. These quad chips on a windows box will easily overclock to 4 ghz with good cooling, a bit of a voltage bump and normal ddr. Nevertheless, this tool is great and I will take what I can get. :)
 
christoh said:
All Mac Pros use ICS932S4xx clock chips. These chips generate 3 independent frequencies.

  • 48 MHz for USB. It cannot be changed.
  • 100 MHz for PCIe, also generates 33 MHz for PCI by dividing the 100 MHz by 3. This can be changed programmatically
  • Bus clock of 333.33 MHz or 400 MHz. Can be changed programmatically.

The bus clock is the speed the front side bus runs with. Since modern FSBs have the quadruple width of the original Intel FSB. Intel says a 400 MHz FSB runs "effectively" at 1600 MHz. I call it "marketing bus clock".

The CPU's speed is determined by the multiplier. A 2.8 GHz CPU has a multiplier of 7. So, if the bus speed is 400 MHz, the CPU runs at 7 * 400 MHz = 2800 MHz.

Memory is also running at bus clock speed. Since DDR2-RAM answers twice per clock cycle, the effective speed is always 2 * bus clock. In stock speed this is 800 MHz.

As you may have noticed, most users here cannot overclock beyond a certain speed, because of limitations in their FB-DIMMs. The CPU would be able to allow even more.

The only way to speed up the CPU while leaving RAM unchanged is to change the CPU multiplier. Most Intel CPUs have this multiplier locked. It cannot be changed. An exception are extreme editions. These have an X in their model number.

The only way to speed up machines with the Intel L5xxx and E5xxx processors is to increase the bus clock. So, that's, what ZDNet Clock does. If you set the bus clock to 450 MHz from 400 MHz you get the following:

FSB marketing speed: 450 MHz * 4 = 1800 MHz (stock speed 1600 MHz)
Memory speed: 450 MHz * 2 = 900 MHz (stock speed 800 MHz)
CPU speed: 450 MHz * 7 = 3150 MHz (stock speed 2800 MHz)

These three speeds are coupled and cannot be changed idependently, except on those machine with an X5xxx processor, where you can increase the CPU multiplier.

We also experimented with the PCIe clock. But switching from 100 to 103 MHz resulted in a coruppted display immediately. This is obviously a syncing problem between the PCIe bus and the PCIe northbridge.

-Christoph
Click to expand...


What is the multiplier for the 3.0GHz and 3.2GHz cpus? I wonder if it is worth to buy the faster cpu and overclock.
 
Ok, I have a version 1.1 MacPro and now the darn thing will not reboot (or it does, over and over, and over and over...) .. anyone know a solution to this mess! :confused:
 
4God said:
Dang! I wonder if there are any benchmarks that would work to indicate any real gains?
Click to expand...

On a MacPro3,1 set the bus clock to no more than 454 MHz. Then warm reboot and run a benchmark (GeekBench, XBench, Cinebench, etc.).

This does not work on a MacPro1,1 or MacPro2,1.

Please see our FAQ, questions 5 and 6.

-Christoph
 
hajime said:
What is the multiplier for the 3.0GHz and 3.2GHz cpus? I wonder if it is worth to buy the faster cpu and overclock.
Click to expand...

On a MacPro3,1 (Early 2008):

2.80 GHz: 7
3.00 GHz: 7.5
3.20 GHz: 8

Formula: Divide the Marketing FSB clock by 4. E.g. 1600 MHz / 4 = 400 MHz to get the true bus clock. Then divide the CPU stock speed by that result, e.g. 3200 MHz / 400 Mhz = 8. That's the multiplier.

Typical maximum safe overclocking is around 460 MHz bus clock (Marketing 1840). This would result in the following:

2.8 GHz -> 3,22 GHz (460 * 7)
3,0 GHz -> 3,45 GHz (460 *7.5)
3,2 GHz -> 3,68 GHz (460 * 8)

-Christoph
 
gatd said:
so Christoph the maximum gain across the range is 15%?
Click to expand...

Sounds accurate. Until they can change the BUS:RAM ratio at least. Then you should be able to push farther. The MacPro has excellent cooling so I wouldn't be surprised to see 2000Mhz FSB (500x4) to 1900Mhz FSB (~480x4) speeds.

You should be able to hit 4 GHz on air. Just not sure about voltages though, the NB may need a voltage bump. It will be easier to find out once the RAM isn't holding you back any more.
 
If you put your Mac Pro to sleep, when it returns is it still at the higher speeds, or do you need to "reboot for changes to take effect"? :)
 
UnixMac said:
Ok, I have a version 1.1 MacPro and now the darn thing will not reboot (or it does, over and over, and over and over...) .. anyone know a solution to this mess! :confused:
Click to expand...

Nevermind, I figured it out... not sure if it was related to this utility or not however.
 
hajime said:
I am going to buy the RAM very soon. Which company's RAM do you recommend in this case?
Click to expand...

Unfortunately I am unable to recommend good overclockable FB-DIMMs as most people don't overclock them.

I guess the tried and true are the Kingston HyperX line and Crucial. The only downside is I don't think you can change the timings and voltage on the memory (HyperX) to be able to take advantage of more speed that it could provide (SPD timings are 5-5-5-18, 1.8V on bootup, but may be overclocked to 4-4-4-12, 2.0V low latency timings Newegg).
 
gatd said:
safely clocked my 3.2 up to 3.7 no problems
Click to expand...

That's a nice bump. On my 3.2 my 8 sticks of ram is holding me back. What Amount of ram and number of sticks do you have? Just the stock apple or any 3rd party?
 
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