To start, this was done in Windows 7 64-bit on an iMac (mid 2010). It uses the 5730m (although Apple refers to it as the HD5670, it’s actually the AMD / ATI Mobility 5730).

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If you’re planning to overclock, it’s a bit of a pain, but here are the quick steps:

1. Grab the latest MOBILITY catalyst drivers from AMD’s website (www.amd.com), and install them.
2. Grab GPU-Z. You’ll be using this to monitor your temps. Can currently be found here: http://www.techpowerup.com/gpuz/
3. Grab MSI Afterburner. AMD/ATI’s “overdrive” is disabled on mobility chips, so you’ll be using Afterburner for the overclocking. Currently, it can be found here: http://event.msi.com/vga/afterburner/download.htm

Once you’ve installed MSI Afterburner, you’ll have to modify the configuration file before it’ll allow you to overclock. WARNING: there’s a reason they make it a pain – you can damage/destroy your GPU very easily with the utility. Overclocking can be quite dangerous. With a mobility GPU it’s particularly risky because if you damage it, you’ll have to spend an insane amount of money to replace the part. It’s often cheaper just to throw the entire machine away. Keep that in mind.

The configuration file is located at C:Program Files (x86)MSI AfterburnerMSIAfterBurner.cfg . The easiest way to edit it is to run Notepad as administrator (right-click, run as admin, then open the file). You’ll be looking for the section called [ATIADLHAL] and changing it to the following (I apologize for the TAB-less spacing – if it doesn’t work, you can figure out the appropriate TAB’s based on the rest of the file):

[ATIADLHAL]
EnableUnofficialOverclocking = 1
UnofficialOverclockingEULA = I confirm that I am aware of unofficial overclocking limitations and fully understand that MSI will not provide me any support on it
UnofficialOverclockingMode = 1
AccessibilityCheckingPeriod = 0

Again, you’re in risky territory now. Ask yourself what you’ll do if your machine’s dead within the next few minutes. If you don’t have a good answer, stop now. Otherwise, you can fire up the Afterburner utility and start overclocking. Watch your temps carefully, and increment slowly. Run some GPU-intensive programs after each change (games, 3DMark, and maybe some stress testing programs like FurMark and OCCT). If your video driver crashes/restarts, or you see any artifacts or any other irregularities, immediately back off your overclock. Note that sometimes, by the time you see an issue it’s too late (the damage is done – I’ve seen this happen to GPU memory many times).

With that over with, here were my results:

Stock GPU Core: 650Mhz  —>  overclocked to 845Mhz (30% increase)
Stock GPU Memory: 795Mhz —> no change

3DMark 11 Score: P1190 —> P1394 (17% increase)

Highest Temp during 3DMark benchmark: 73.0C —> 74.5C

Dragon Age 2 Demo (DX9): 51.5 FPS —> 60 FPS (17% increase)
Dragon Age 2 Demo (DX11): 32 FPS —> 35.5 FPS (11% increase)

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You’ll notice the core overclock was pretty hefty – a whopping 30% increase. It survived the DA2 demo, a FurMark benchmark,  and 3DMark. None of these ran for extraordinary lengths of time however, so it’s possible instability might show up after some time. I also tried a core speed of 875Mhz, but it didn’t make it through 3DMark. Things seemed to work well at 845Mhz, so I kept it there.

I’d tried bumping up the memory speed a bit, but it didn’t have a positive effect in 3DMark (going from 795Mhz to 820Mhz anyway). Since GPU memory’s often particularly easy to kill, I didn’t try going any further. Technically, I’d seen a minor decrease with the memory overclock (from a P1394 rating down to P1388), so I didn’t see much point in risking higher clocks if I wasn’t seeing any gains.

The frame rates in Dragon Age 2 were taken with the demo paused right as the first combat begins. The FPS fluctuates wildly, so hitting pause 1 second in was the closest I came to getting some consistency for the DX9 run (it crashed if I alt-tabbed and changed the video card’s overclock on the fly).

The DX11 run for DA2 was a little more forgiving in terms of consistency. I could pause it, alt-tab, bump up the clock rate, and alt-tab back into the game and see the frame rate result immediately. It’s worth noting that I also tried bumping up the memory a bit at a time through this process (since results were quick), eventually getting from the base of 795Mhz up to 870Mhz before chickening out about going further. I tried this at a few points – in the best case I got from 36.5fps to 39.5fps, and in a more typical case, from 25fps to 25fps (no change). Really, there’s very little to be had by overclocking the memory from what I can tell. It’s possible that a massive overclock would be more worthwhile, but I wasn’t willing to risk it.

Conclusion:

There are certainly gains to be had, but whether it’s worth the risk is debatable. A 30% overclock looks great on the surface, but it only translated to an 11-17% increase in fps/ratings. The biggest problem with this (and with overclocking in general) is that it helps the most when your frame rate is already high. If you’re dancing around low FPS numbers it doesn’t amount to much. A game that pulls 100FPS won’t look much better at 111FPS (even though it’s an 11FPS increase), and a game running at a painful 20 FPS isn’t going to seem magically better at 22 FPS (even though it’s an 11% increase).

On top of that, it’s very high risk. If you kill a $100 video card in a regular machine, you can just buy a new video card – maybe even a faster one. If you kill the mobile GPU in your laptop (or iMac), it’s going to cost you a fortune to get it replaced, and you usually don’t have the option of a faster one.

That said, those were my results. If you’ve got the 5730m and are considering overclocking it, hopefully the results above help you. Note however that if you’re using a laptop, you might have much higher temps than I did (and hit an overclocking ceiling or a “disaster zone” much earlier), since laptops generally have poor cooling capabilities, whereas the iMac I was using is essentially one massive aluminum heatsink. Depending on the manufacturer, your chip might be clocked differently, or at a different voltage. Definitely test at your own rate – don’t simply plug in my final numbers and cross your fingers – slow incremental changes are best.

Rather than going for a maximum overclock, you might want to simply stop once you’ve gone far enough that you’re content with your gains.

After all, while you’ll often see temporary indications that you’ve overclocked too far, there are other times that you quickly find out your GPU just lost a permanent game of russian roulette.