Galaxy GeForce GTX 560 Ti GC Overclocking Review

We take an in-depth look at overclocking the new Galaxy GeForce GTX 560 Ti GC with XtremeTuner HD. We compare performance against the Radeon HD 6950 in apples-to-apples testing. Find out what 1GHz+ frequencies can do for the GTX 560 Ti’s performance.


On January 25th 2011 NVIDIA debuted the new GeForce GTX 560 Ti. We evaluated a retail Galaxy GeForce GTX 560 Ti GC which bolsters a slightly higher core frequency, custom cooling, a custom printed circuit board, and the potential for a high level of overclocking. In our initial evaluation we did not have the time required to go in-depth on overclock testing. This article is a follow-up to our evaluation that focuses on overclocking the Galaxy GTX 560 Ti using XtremeTuner HD from Galaxy.

To learn all about what the Galaxy GTX 560 Ti GC has to offer in terms of gameplay performance, and especially how it compares to the Radeon HD 6950, please read our evaluation of the video card first. This article is going to use apples-to-apples comparison testing at the same settings. We are going to compare the Galaxy GTX 560 Ti Overclocked to the Galaxy GTX 560 Ti at default speeds and then finally to the Radeon HD 6950. What we want to know is if the Galaxy GTX 560 Ti GC can equal or exceed the Radeon HD 6950 in performance when highly overclocked.

Test System: The test system is the same exact setup from our previous evaluation. MSI Eclipse X58, Intel Core i7 920 overclocked to 3.6GHz, 6GB of DDR3 and a Dell 3007WFP. We are using the provided ForceWare 266.56 Beta drivers and Catalyst 10.12a Hotfix. We contacted AMD about changes made to Catalyst 11.1a Hotfix to see if any games we are using here received a performance boost with the newer driver. It was reported that none did, so we did not need to re-test performance for these games below using the new driver.

XtremeTuner HD

In order to overclock the Galaxy GTX 560 Ti Galaxy offers a program called XtremeTuner HD. The latest version of XtremeTuner HD on Galaxy’s website does not support the new GTX 560 Ti GPU. We had to use the provided version on the CD which is version 3009, the website contains version 3008.

Article Image

The default configuration is quite simple. The interface shows you how many CUDA Cores are at play, the driver version, the BIOS version, and a quick to look at temperature reading of the GPU in the right hand corner. Underneath are rows of sliders that let you change memory voltage (when supported), core frequency, shader processor frequency, memory frequency, fan speed and core voltage (when supported.)

You will note that the core frequency and shader processor frequency are locked, this is because the shader processor frequency operates on a ratio of the core frequency, they are bound together. When you overclock the core, it also overclocks the shader frequency equally. Thanks to the Galaxy GTX 560 Ti GC and XtremeTuner HD, these can be unlocked however. Therefore, you can adjust both the core and shader frequency separately, manually. This will allow you to fine tune overclocking. Remember, the core frequency affects the ROPs and everything else, while the shader frequency affects the CUDA Cores.

The program also allows you to bring down a bunch of graphs that show you temperature, fan speed, and clock speed readings over time. The program allows you to save profiles you have created of clock speeds as INI files. These files can be saved anywhere and you simply load the profiles and it sets the clock speeds. The Galaxy GTX 560 Ti GC also supports Magic BIOS which lets you burn the clock speed and voltage settings onto the BIOS so they are hard coded into the video card. Finally, there are built in 2D and 3D performance profiles by default, which can of course be changed and saved.

Article Image

XtremeTuner HD allows a wide range of slider options, which we are happy to see. The core frequency slider allows all the way up to 2GHz core frequency and 4GHz shader frequency. The memory slider allows up to 3600MHz which would be 7.2GHz GDDR5 speeds. The core voltage allows up to 1300mv worth of headroom. Unfortunately, the core voltage slider seems to be locked at a maximum of 1150mv for us. We could not apply changes past 1150mv, so that is the cap we were presented with for voltage increase.

Article Image Article Image

The 2D frequency profile sets the GPU at quite low frequencies, 50MHz core frequency, 101MHz shader frequency and 135MHz memory frequency. The core voltage also drops to 950mv. This is one reason the video card idles so well. There is a lower power and noise profile called "3D Low" which sets the core to 405MHz, shaders to 810MHz and memory to 324MHz also with the lower core voltage. By default, the video card operates in "3D Performance" profile which are the default clocks of the video card.

Highest Stable Overclock

Overclocking was very simple on this video card using XtremeTuner HD. We simply ramped up the clock speeds and voltages and played all our games to see what was stable. Before we messed with over-volting the core we wanted to see what the maximum overclock was without any modification.

Overclock with NO Modification

Article Image

The above screenshot is a result of our overclocking attempts without over-volting the core. We managed to get the core frequency up to 975MHz (vs. 835MHz) and the shader frequency up to 1950MHz (vs. 1670MHz.) The memory overclocked up to 2170MHz (4.34GHz GDDR5) vs. 1000MHz or 4GHz. Right off the bat, we were not able to get this video card to the coveted 1GHz barrier without increasing the voltage. It is only when we did increase the voltage that we achieved beyond 1GHz.

Overclock WITH Modification

Article Image

The screenshot above is a result of our highest stable overclock with increasing the core voltage. The core voltage is at 1000mv by default, and we took it to the maximum value the program would allow, which is 1150mv. Interestingly, we also installed a reference NVIDIA GeForce GTX 560 Ti to look at overclocking comparisons and found its core voltage to be higher than the Galaxy GTX 560 Ti. Indeed, a reference NVIDIA GeForce GTX 560 Ti has a default core voltage of 1012mv. This is interesting because the Galaxy GTX 560 Ti is running a slightly higher clock speed, but yet a lower core voltage.

By increasing the core voltage to 1150mv we were able to increase the core frequency to 1015MHz and shader frequency to 2030MHz. The memory voltage slider was grayed out so we could not adjust the frequency of the memory and obtain a higher value.

You will notice that the fan slider is maxed out at 100%. We did NOT change the value of the fan slider, we simply left it on automatic. This screenshot above is a result of us playing Battlefield: Bad Company 2 with this overclock. We played the game for 30 minutes and took a screenshot of XtremeTuner HD so you could see what it looked like with a game running at full tilt with the overclock. What you see is that the fan automatically ramped up to 100% fan speed. The core temperature also rose to 83c while gaming. Even though the fan was running at 100%, it was still not a loud solution. While we could hear the rush of air being moved, it was not annoying, and honestly not that much louder than our CPU or case fan running. It is a very quiet solution even at 100% fan speed.

Article Image

Therefore, our overclocking results end up looking like this above. Needless to say, it is quite exciting to achieve a frequency past 1GHz. Again, this was only possible by over-volting the core. This GPU seems to respond well to voltage increases correlating to frequency increases.


Article Image

We took power and temperature measurements with the overclock. The overclock does not come cheap as our full load system Wattage rose to 516 Watts versus 433 Watts at default. This overclock with this video card adds about 135 more system Watts than the system running an AMD Radeon HD 6950.


Article Image

Temperature also increased by 15 degrees up to 83c. This temperature of 83c is still cooler than the Radeon HD 6950, thanks to the custom cooler on the Galaxy GTX 560 Ti GC. In fact, considering the clock speeds and the voltage increase, we are quite impressed by these temperatures. Keep in mind though the fan was running at 100% with these temperatures, therefore, it is at its limit as far as cooling is concerned.