Overclocking & Tweaking

Overclocking & Tweaking

As most of you with most videocards know, you can apply a simple series of tricks to boost the overall performance a little. You can do this at two levels, namely tweaking by enabling registry or BIOS hacks, or very simple, tamper with Image Quality. And then there is overclocking, which will give you the best possible results by far.

What do we need?One of the best tool for overclocking NVIDIA and ATI videocards is our own Rivatuner that you can download here. If you own an ATI or NVIDIA graphics card then the manufacturer actually has very nice built in options for you that can be found in the display driver properties.

Where should we go?
Overclocking: By increasing the frequency of the videocard's memory and GPU, we can make the videocard increase its calculation clock cycles per second. It sounds hard, but it really can be done in less than a few minutes. I always tend to recommend to novice users and beginners not to increase the frequency any higher then 5% of the core and memory clock. Example: If your card runs at 600 MHz (which is pretty common these days) then I suggest you don't increase the frequency any higher than 30 to 50 MHz.

More advanced users push the frequency often way higher. Usually when your 3D graphics start to show artifacts such as white dots ("snow"), you should back down 10-15 MHz and leave it at that. Usually when you are overclocking too hard, it'll start to show artifacts, empty polygons or it will even freeze. Carefully find that limit and then back down at least 20 MHz from the moment you notice an artifact. Look carefully and observe well. I really wouldn't know why you need to overclock today's tested card anyway, but we'll still show it ;)

All in all... do it at your own risk.

Now here's where things get even more interesting. The reference GTX 285 seems to be a nice overclocker, but things get hard with the pre-overclocked models

We used Rivatuner 2.22.

Core Frequency:

• The reference clock for the GTX 285 is 648 MHz, we ended up at ~700MHz.

Shader Frequency

• The shader domain clock for the GTX 285 is 1476 MHz, we ended up at 1584 MHz.

Memory Frequency:

• The memory clock for the GTX 285 is 2484 MHz (effective), we ended up at 2600 MHz yet don't be surprized to reach 2800 MHz.

The GTX 285 will overclock on the fly. Fact is you will not get it much faster than the clock frequencies mentioned above. All of today's tested product, where already clocked at such speeds. But expect to reach roughly a 700 MHz core, ~ 1500 MHz on the Shader domain and 2500 to 2600 MHz on the memory. Which makes it a fairly decent product series to overclock.

Now there was one exception to the rule, eVGA has tweaked the BIOS and likely applied some higher voltages to ensure more stable overclocks. As a result their product overclocked disproportional higher on memory and slightly more on the core/shader domain:

• 745 Core | 1681 Shaders | 2928 Memory (effective).

Especially the memory was astounding and reaching close to 3 GHz. I planted the results in this chart:

Now coming from a reference clocked GTX 285 .. that's a pretty extensive overclock you guys. This is BIA: Hell's Highway again by the way (same setup and image quality settings).