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spcdust

macrumors 65816
Original poster
May 6, 2008
1,087
162
London, UK
Out of interest are any of you over clocking your GPU using the Catalyst Controller Overdrive function? I've done a comparison between the default settings and then cranking up the GPU Clock settings to the maximum allowed Overdrive settings here are the results:

Default Settings (680MHz GPU Clock / 900MHz Memory Clock)


Overdrive Settings (710MHz GPU Clock / 1000MHz Memory Clock)

It's not a huge leap but still squeezes a little more from the GPU.

I always have my fans set to an average of 1820RPM when gaming so using the overclock settings I'd hopefully keep the GPU suitably cooled - any opinions?
 

spcdust

macrumors 65816
Original poster
May 6, 2008
1,087
162
London, UK
Why on earth are you overclocking a mobile version GPU?

These are the "overclocking" functions that are part of AMD's own Cataylist Driver software - the manufacturer of the GPU. As these are integrated as part of Catalyst Software one imagines AMD/ATI feel these settings are okay. Just to clarify, this is in Windows 7 (Bootcamp) and I'm not using third party programs, just AMD's / ATI's own driver software.
 

dndlnx

macrumors 6502
Dec 9, 2010
332
0
These are the "overclocking" functions that are part of AMD's own Cataylist Driver software - the manufacturer of the GPU. As these are integrated as part of Catalyst Software one imagines AMD/ATI feel these settings are okay.

That's some great logic. Carry on, I guess.
 

spcdust

macrumors 65816
Original poster
May 6, 2008
1,087
162
London, UK
That's some great logic. Carry on, I guess.

Not sure if your last post is sincere or a little sarcastic, if the latter then that's a bit of an attitude you've got there fella.

I was seeking constructive discussion on the point I raised, if you have any knowledge then feel free to share, if you no not what you are talking about then that's also fair enough but then possibly best not to contribute to a valid post. Are you still using the antiquated GPU drivers included in Boot camp as anyone with a little savvy immediately jettison these for the newer manufacturer supplied Drivers to unleash their GPU's potential. Plenty of people have also been successfully over clocking their GPU's in the iMac and MacBook Pro's when on the Windows side of things with no detrimental damage - however I'm not interested in going down the unofficial third party route and changing the GPU's voltage etc. I'm just tweaking the supplied settings included in the manufacturers driver software whilst giving the fans a boost, using SMC fan control, for cooling as the fan management on the Windows side of things has always been a little lacking.
 

0098386

Suspended
Jan 18, 2005
21,574
2,908
Why on earth are you overclocking a mobile version GPU?

I've overclocked my x1600 iMac since 2006, pushed it to the absolute limit. Any further would have artefacts. Never had a problem with it (I pumped in 600 hours of TF2, 500 hours of L4D1, 200 of L4D2).

I'd be tempted to overclock my 6970 but I'm reluctant to do anything that may void my Applecare this time :eek:.
 

laserbeam273

macrumors 6502
Sep 7, 2010
424
0
Australia
Can you overclock on OS X? My GPU seems to be the lag in my set up, 2.8 GHz i7 iMac 2011... CPU doesn't run that hard during gaming, but I bet my GPU is cranking it.

Though I'm not sure I want to overclock... I'd have to do it ever so gently, be able to monitor the temps constantly, and probably jack up the fan speeds a healthy portion. I'd hate to bust my computer though.
 

spcdust

macrumors 65816
Original poster
May 6, 2008
1,087
162
London, UK
Can you overclock on OS X? My GPU seems to be the lag in my set up, 2.8 GHz i7 iMac 2011... CPU doesn't run that hard during gaming, but I bet my GPU is cranking it.

Though I'm not sure I want to overclock... I'd have to do it ever so gently, be able to monitor the temps constantly, and probably jack up the fan speeds a healthy portion. I'd hate to bust my computer though.

I'm 99% sure you can't overclock the GPU drivers in OSX but happy to be corrected.
 

NMF

macrumors 6502a
Oct 27, 2011
885
21
Out of interest are any of you over clocking your I always have my fans set to an average of 1820RPM when gaming so using the overclock settings I'd hopefully keep the GPU suitably cooled - any opinions?

How are you setting your fan speeds? The option is grayed out for ME in CCC. Unless you're using MSI Afterburner or something?
 

spcdust

macrumors 65816
Original poster
May 6, 2008
1,087
162
London, UK
How are you setting your fan speeds? The option is grayed out for ME in CCC. Unless you're using MSI Afterburner or something?



I set my fans speeds using SMC Fan Control whilst in OSX and then reboot into Windows - as long as you reboot and don't shut down the fan speeds you have set are remembered.
 

Hellhammer

Moderator emeritus
Dec 10, 2008
22,164
582
Finland
I'd be tempted to overclock my 6970 but I'm reluctant to do anything that may void my Applecare this time :eek:.

Overclocks are purely software and hence untraceable. Apple has no way of proving that you have overclocked your Mac, so warranty will not be voided.

I'm 99% sure you can't overclock the GPU drivers in OSX but happy to be corrected.

I would say it's possible in theory but nobody has gotten around of it. IIRC Cindori looked into it and his Zeus app has some NVIDIA OCing tool in it but not sure if it worked. Games run better under Windows anyway.

I set my fans speeds using SMC Fan Control whilst in OSX and then reboot into Windows - as long as you reboot and don't shut down the fan speeds you have set are remembered.

MacFan works in Windows.
 

0098386

Suspended
Jan 18, 2005
21,574
2,908
Overclocks are purely software and hence untraceable. Apple has no way of proving that you have overclocked your Mac, so warranty will not be voided.

Thanks! I might do a bit of testing tonight then :).

Does it make any real difference at all when gaming though?

Oh my yes.
On my x1600 iMac gaming under the default clocks was tough. Once I added 200mhz to the clock speed (Apple underclock them) I was playing at a good res, but still low settings, for a smooth 60fps. Definitely worth it!
 

Jethryn Freyman

macrumors 68020
Aug 9, 2007
2,329
2
Australia
Overclocks are purely software and hence untraceable. Apple has no way of proving that you have overclocked your Mac, so warranty will not be voided.
This man speaks the truth.



I would say it's possible in theory but nobody has gotten around of it. IIRC Cindori looked into it and his Zeus app has some NVIDIA OCing tool in it but not sure if it worked. Games run better under Windows anyway.
You can overclock of Power PC Macs using ATIccelerator.


Does it make any real difference at all when gaming though?
I can get a ~20% increase in performance without a loss of stability on my Power Mac G5...
 

henrikrox

macrumors 65816
Feb 3, 2010
1,219
2
While ati overdrive is fine. You should not use it for overclock, because its pretty limited of what you can do/how much you can overclock.

Now, i would not worry when overclocking the gnu in the iMac, i overclocked the 2010 and the 2011 iMac with great results.

And with the 2011 iMac with the 6970, you can easily go 800 gpu clock / 1000 memory.

Gpu clock matters much more when it comes to squeezing out some extra frames per second.

Anyways, it could be wise to set your fans to like 2k+ before gaming and keeping an eye on temperatures etc with a alt tab once in a while.

The gpu can overclock even further, but the problem then becomes power consumption. It draws to much power and the iMac will show its not stable.
also, turning up the voltage could be dangerous if you don't know what you are doing, so thats not recommended.

But a safe 800 / 1000 is easily achievable
 

DJJAZZYJET

macrumors 6502
Jun 4, 2011
459
144
I set my fans speeds using SMC Fan Control whilst in OSX and then reboot into Windows - as long as you reboot and don't shut down the fan speeds you have set are remembered.

This is exactly what I do. Set my SMC fan control in OSX then restart in windows, use AMD Overdrive to squeeze some extra frames. To really get all the power out, I defrag alot, and use Gamebooster which makes lots of different tweaks that optimize the gameplay. I keep my SMC fan controls on max as things will get pretty hot whilst playing games, to keep everything very cool (yes its loud, but i use headphones) Im just wondering if there are any other tweaks or programs that people use to help their gameplay?
 
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