Overclocking continued

Once you have the card running at default 3D clocks/voltages and you understand the risks associated with overclocking, the time for the real overclocking starts. Overclocking the X1900 is just like any other ATI card except for the fact that you can control the voltages of the card with ATITool. You first need to keep in mind that ATITool is a tool and understanding that tools are only as good as the way you use them. Simply clicking on find Max and expecting it to do everything for you just isn't going to always work. Since the whole find max is not an exact science you may encounter issues. However the following steps should get you started towards overclocking your video card using ATITool.



At this point you should be familiar with stopping the correct services, change voltage to 3D clocks and change the clocks themselves. Often, but not always the 'Find Max' will lock the system up, this is not a show stopper and can be to your benefit. Now you know at which speed the card is no longer stable. As shown below when we restart ATITool it tells us at what speed the tool crashed.



From here you have a couple of options, one of course would be to raise the voltage and the second verify your temperatures and or raise the fan speed. Remember the most important thing you can do to enable a good overclock is watch the temperatures and this becomes really important in regards to the voltage regulators that in most cases, if not all you will need to add a fan to keep them cool, this also relates to the longevity of your video card. So the first option to increase voltage has a direct affect on temperatures, obviously the higher you go the hotter it will get. It's up to you to manage the increase in temperatures and this will in most cases determine your final overclock.

With that let's move on with the settings we last reached before we crashed or if ATITool reached a max clock speed of either core or memory you can move on to test your new overclock. The max clock speed of 735 was the last core speed reached and if you are at a stopping point in regards to the max amount of voltage you want to use you can try what I recommend and subtract 10 to 15 MHz from that speed to set the limit at which ATITool will go during 'Find Max'. This is done by going into settings and selecting 'Overclocking' to set safety range.


For the Diamond Viper X1900XT I used the following voltage settings above for the core and memory to get my GPU / Memory speed for the overclock benchmark runs of 720/810 MHz. After considering higher temperatures I settled on those voltage settings and clock speeds and tested these settings by running the 'Find Max" for both core and memory for around an hour, after which you can then further test your settings by combining both GPU / memory overclocks by playing some graphically intense games for an extended period of time.


Of course not all cards overclock the same and your experience may vary. Also increasing voltage does not always equate to more speed in some circumstances, the trade off for a few more MHz is negated by a rise in temperatures.