Step One: Do Your Research
Before you do anything else, you should hop on over to Google and do some research on your card. Sift through sites like Overclock.net
and see what kind of clock speeds other people are getting. Do NOT just
apply these clock speeds and start benchmarking—every single card is
different, and even someone with the exact same model card will get a
different overclock from the next guy or girl. The goal here is to see
what other people are getting so you know what's reasonable—that way, if
you get way higher than everyone else, you know something probably
isn't working correctly.
While
you're at it, find out what the highest safe voltage is for your
card—that'll come in handy when we start pushing the voltage. I'm using
the word "safe" loosely here—obviously, the only truly safe voltage is the default, and increasing it can decrease the lifespan of your card.
Lastly,
if you have a newer, high-end card—especially one of the NVIDIA Kepler
cards—some of your settings will be different than they are for other
cards. If MSI Afterburner looks a little bit different for you, be sure
to research a guide for your own card to see what each of the settings
mean.
Step Two: Benchmark Your Card
Open MSI
Afterburner and take note of your stock speeds. Before you start
overclocking, you should run Heaven one time through to make sure your
card is stable at stock speeds. You'll also get a benchmark score, which
is a great way to measure your progress as you overclock. Here's what
you need to do:
- Start Heaven, and you'll be greeted with its initial settings menu.
- Tweak
its settings however you want. I usually like to set Quality,
Tesselation, and Anti-Aliasing to their maximum values, since I have a
midrange card, but if you're overclocking a lower-end card, you may not
need to push the settings so far. Make sure that Resolution is set to
"System."
- Click
the Run button. Heaven will start cycling through a series of scenes
designed to push your graphics card to its limit. Don't worry if it
seems slow or choppy—that's what we want.
- Click
the "Benchmark" button in the upper left-hand corner of the screen to
run a benchmark. This will go through all 26 scenes one time, measuring
your card's performance.
- When
the benchmark is done, you'll see a window with your score on it. I
like to write this down so I can compare it to my post-overclocking
scores.
If your card made it through the benchmark run, rejoice! Your card is, at the very least, stable at stock settings.
Step Three: Raise Your Clock Speeds
You've been
patient up until this point, and it's time for your reward: you can
finally start overclocking (that's why you're here, right?). Open MSI
Afterburner and raise your core clock by 10MHz or so (make sure the
shader clock is linked to the core clock, if you have it). Click Apply
to apply the settings, then ensure they've been applied by checking
GPU-Z and seeing if it matches. You should also click Save in MSI
Afterburner, and assign your new settings to one of its profiles.
Now,
run Heaven again, and just like before, click the Benchmark button. If
it makes it through the benchmark run without any problems, your
overclock is stable and you can raise the core clock by 10MHz again.
At
some point, however, you'll run into some issues. Either Heaven will
give you a black screen and stop working, or your graphics driver will
crash, or you'll start seeing "artifacts" on the screen—little graphical
glitches that aren't supposed to be there. These could be little black
boxes, colored lines and blotches that appear on the screen, and so on.
If
you run into any of these problems, your overclock is unstable. You now
have two choices: you can back off to your last stable core clock and
skip to step four (for a very small overclock), or you can raise your
voltage.
Step Three Point Five: Raise Your Voltage
When you
reach a certain point, your card needs more voltage before it can run at
certain speeds. Raising your voltage past the stock level can push your
card significantly farther, but it can also decrease the lifespan of
your card (especially if you push it too far). So, you should only go
through this step if you're willing to take on that risk.
By
default, MSI Afterburner locks the voltage on your card so you can't
raise it. So, in order to tweak the voltage, you need to open up MSI
Afterburner's Settings and, under the General tab, check the "Unlock
Voltage Control" box. Click OK and you should see a new slider at the
top of Afterburner's main window.
Increase
your voltage by 10 mV or so and click Apply. Afterburner may change the
value slightly; it appears that it only works with certain voltage
values, so you'll get a number close to the one you typed in. Now, start
a benchmark run in Heaven again. If you make it through without any
artifacts or crashes, your core clock is stable and you can try raising
it again
Repeat this
process. Run Heaven, increasing the core clock after each stable run.
When you have problems, increase the voltage and try again. Watch your temperatures
as you do so. As you raise the voltage, your temperatures will start to
get higher. Most modern cards are safe at around 90 degrees celsius,
and Afterburner's automatic fan control will try to keep the temperature
below that level. If you want to be more conservative (I usually try to
keep it in the 80s), you can tweak Afterburner's fan control in the
settings, under the Fan tab.
Eventually, you'll reach to a point where you can't overclock any further. This usually happens for one of three reasons:
- You reach unsafe temperatures for your video card and can't cool it any better.
- You reach the maximum safe voltage for your card (which you researched earlier).
- Your
card just isn't stable past a certain core clock value, no matter how
high you raise the voltage. This can happen if you have a card that just
doesn't overclock well (remember, no card is guaranteed to
overclock—it's luck of the draw!)
When that point comes, back down to your last stable clock speed. This is your highest possible core clock.
When you're done with the core clock, repeat this entire process with the memory clock.
Your memory clock speeds won't get you as big of a performance boost as
core clock will, but it's worth raising, especially since you've gotten
the hang of the process by now.
Step Four: Stress Test Your Card
Once you find your highest possible overclock, you should do some more
intense stress testing. Start Heaven, click the Run button, and just let
it run instead of clicking the "Benchmark" button. Let it run for a few
hours (five or so should be fine) and, if you don't experience any
crashing or artifacts, you can consider your overclock stable. Do a
benchmark run and compare your score to the one we got in step two if
you want to see how much your card has
improved!
Step Five: Game On
Of course, while Heaven is a good benchmarking tool, the best
way to test your new card is to play a game! Fire up a game that's
really graphics-intensive—like Battlefield 3, Skyrim, or Crysis 3—and
see how it fares. Try to find a level with a lot of stuff going on, so
it pushes your GPU pretty hard. Again, if you don't have any problems,
you're good to go. Of course, if you're ever gaming and you come across
artifacts or regular crashing, try backing off your overclock and seeing
if that helps. Sometimes an overclock is "benchmark stable" but just
doesn't quite cut it in games.
