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Overclocking The ATI Card Via D.O.T.

Graphics Overclocking: Getting The Most From Your GPU
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Before we begin, a word of warning is in order. Overclocking may damage your card, and if you make any changes, you do so at your own risk. Doing so may also void your warranty.

MSI calls the overclocking feature it integrates into its modified driver version D.O.T. (Dynamic Overclocking Technology). In all, it offers six different settings. However, that doesn’t mean that all of them are guaranteed to work. Also, despite what some of the settings may imply, D.O.T. is limited to the maximum clock speeds of 790 MHz (GPU) and 1,000 MHz (memory) that ATI’s driver offers. There is no way to say in advance whether a certain setting will work with the card you end up buying, since the variation from one card to the next are too large, even with cards from the same production batch.

O/C Mode
Clock Speed (GPU/Memory in MHz)
Standard (default)
750/900
MSI D.O.T Private
765/918
MSI D.O.T Sergeant
780/936
MSI D.O.T Captain
790/954
MSI D.O.T Colonel
790/972
MSI D.O.T General
790/990
MSI D.O.T Commander
790/1,000


As long as the setting you choose actually works, you won’t actually feel a difference, aside from the performance, obviously. If your card features an optimized fan speed profile, like our MSI card does, the fan will spin up to deal with the extra heat generated by the higher clock speeds. The change shouldn't be dramatic, though, and you’d probably need a noise meter to tell the difference. Normally, the graphics driver also lets you keep tabs on the fan speed, allowing you to check whether your card is reacting to the changes. MSI’s modified driver didn’t offer this option. Besides, even if you upgraded to ATI’s current Catalyst 9.6, you still wouldn’t be able to switch back to the driver software fast enough from within a 3D game to take readings from the Catalyst user interface, since the fan speed drops immediately when there is no 3D load.

GPU monitoring with GPU-ZGPU monitoring with GPU-Z

If you want to keep an eye on your GPU’s temperature, we recommend a free tool called GPU-Z that can also monitor fan speeds, clock speeds, and some of your graphics card’s various other vital signs. It can also create a log file, which is very handy if you want to check back on your card’s performance later.

Since you’ll only know you’ve found the ideal setting after the fact (namely when you go over the log files or push your board one level too far), it’s best to keep your initial tests short. Normally, a GPU will reach its maximum temperature under load after two to five minutes. You should also take some readings at stock settings, allowing you to check on what’s changed and to what extent. If the fan does not spin up, you need to keep a very close eye on the temperature. The current generation of graphics chips usually begins throttling performance back once they reach critical temperature. In practice, your GPU’s temperature should not exceed 90 to 100 degrees Celsius.

ASUS Smart DoctorASUS Smart DoctorAsus‘ Smart Doctor utility doesn’t give you all that much help either. You’ll still need to experiment on your own until you find the right settings. To reduce the risk of damaging your card, you should start off with the smallest overclocking increment and apply the change. Then switch to a 3D benchmark to stress the GPU with the new settings. Ideally, combine a high resolution with anisotropic filtering (AF) while leaving anti aliasing (AA) disabled. You’ll know when you’ve exceeded your card’s limit if you see any of the following symptoms: rendering errors, inverted colors, a flickering screen, pixelation, solid blocks of color, or a frozen system. At that point, your graphics driver may restart, dumping you back to the desktop. Alternatively, your system may crash completely and restart, in which case you can forget about the increased clock speed.

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