As most of you know, with most videocards 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 simply to 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 tools for overclocking NVIDIA and ATI videocards is our own AfterBurner which will work with 90% of the graphics cards out there. We can really recommend it, download here.
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, to not increase the frequency any higher than 5% on the core and memory clock. Example: If your card runs at 600 MHz then I suggest that 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.
The Radeon HD 7870
Core Clock: 1000 MHz
Core Clock: 1100 MHz
Core Clock: 1227 MHz
Shader Clock: 1000 MHz
Shader Clock: 1100 MHz
Shader Clock: 1227 MHz
Memory Clock: 4800 MHz
Memory Clock: 4800 MHz
Memory Clock: 5800 MHz
For the HIS R7870 we open up AMD Overdrive or AfterBurner and free the card up from TDP restrictions first, so all the way down move the Power Control settings slider towards 20%.
Overclocking wise the card will allow itself to be clocked to roughly 1150 MHz on the core easily and that's without voltage tweaking. We were actually able to push the card towards a nice 1150 MHz on the GPU core. Memory can be boosted as well, just max it out at 5800 MHz.
Now if you apply a little extra voltage with say Afterburner, then put it at roughly 1250Mv... now you can tweak a bit more out of the GPU. You will need to increase fan RPM a bit though.
Below, are some numbers based on the overclock we were able to pull off. Both cards are very flexible in terms of overclocking alright. Granted, the entire Radeon HD 7000 series is a gem when it comes to tweaking.
Above, Crysis 2, same maxed out image quality settings as before yet now with added overclock results:
High Resolution Texture Pack
Ultra Quality settings
Level - Times Square (2 minute custom time demo)
Above, 3DMark 11 - the Performance test and score. As you can see, there is an additional bump in this very GPU limited software, lovely.
Above, Alien versus Predator, at 1920x1200 with 4x AA and 16X Anisotropic Filtering
HIS Radeon R9-290X review In this review we test the HIS Radeon R9-290X. The product is based on the reference design of the original Radeon R9-290X. These cards are little beasts. As such this in-depth review will cover the V...
HIS Radeon R9-280X IceQ X2 Turbo review In this review we look at the Radeon R9-280X IceQ X2 Turbo review from HIS. Armed with a customized PCB and their top model IceQ coolers they factory overclocked the product and will try to get you as much value for money as they can. Follow us into this review where we'll look at temperatures, noise, performance, Frame latency and we'll even give Ultra High Definition gaming a go with the hottest game titles on the globe.
HIS Radeon HD 7950 HIS IceQ X2 review We test and review the a HIS Radeon HD 7950 HIS IceQ X, this 30 CM sized beast is one heck of a graphics card. Custom PCB, custom cooling, it's low noise and being a Boost edition card series, it clocks in at 950 MHz.
HIS Radeon HD 7850 4GB iPower IceQ Turbo review We test and review the a HIS Radeon HD 7850 iPower IceQ Turbo as single card and in Crossfire today. The HIS Radeon HD 7850 iPower IceQ Turbo is a factory overclocked 4GB version of the Radeon HD 7850 graphics card.