OverclockingOverclocking
Overclocking
30 MA XIMUMPC MARCH 2006 MARCH 2006 MA XIMUMPC 31
Overclocking Athlon 64: Step-by-Step
We fi red up one of our favorite Athlon 64 mobos—a DFI LanParty SLI Ultra-D—and cranked it up a notch in
the name of science. A lot of AMD boards include overclocking utilities that let you change settings from within
Windows, but we’re doing it the old-fashioned way, through the BIOSSTEP 1: ENTER THE BIOS
Before you attempt to overclock your rig, make sure you
back up your important fi les. Overclocking too far can cor-
rupt your fi les. Once you’ve backed up your data, you can
venture into
the BIOS.
This Phoenix
BIOS is
standard
fare, and will
look familiar
to BIOS
veterans.STEP 2: LOCATE THE RIGHT MENU
Under the section labeled Genie BIOS Setting, we fi nd the
Holy Grail:
“FSB Bus
Frequency.”
That’s the
one. Let’s
open it up
and see
what our
options are.STEP 3: INCREASE THE FSB
Here we have the optional
FSB frequencies, in handy-
dandy 1MHz increments.
That’s just the way we like it,
because it allows for a very
fi ne level of tuning. Let’s crank
up the FSB a conservative
3MHz, which should boost
our CPU clock about 40MHz.
Remember, 3MHz (the FSB increase) times 12 (the CPU multi-
plier) equals 36MHz—not too shabby!STEP 4: IT’S ALIVE
After making the changes,
we rebooted. It posted,
and we see here we have
successfully overclocked
from 2.4GHz to 2.44GHz!
Because the BIOS rounds up, it’s reporting a 40MHz jump.
Now repeat Steps 3 and 4 until your system doesn’t boot any-
more, and then jump down to Step 5.STEP 5: START OVER FROM SCRATCH
When your machine ceases to boot, reset the CMOS via
the jumper on the motherboard. For reference, it’s typically
located near the CMOS battery. You can also just remove the
battery for a few seconds if you can’t fi nd the reset jumper.STEP 6: GIVE ‘ER MORE JUICE
If you fi nd yourself hitting the wall and your rig won’t overclock
any higher, you can try increasing the CPU’s core voltage. On
our DFI board, this is possible through the CPU VID control.
Start out with extremely tiny steps, and don’t increase the
voltage more than 10 percent. For example, if core voltage is
1.4V, don’t go higher than 1.5V. Tweaking your voltage can fry
your CPU, so if you’re nervous, just leave it set to “auto,” and
crank your CPU clock down a notch or two.BEST AMD PROCESSORS FOR
OVERCLOCKING
X2 ATHLON 3800+ This 2.0GHz entry-level dual-core proc has
been known to go all the way up to 2.6GHz.SEMPRON 3100+ It ships at only 1.8GHz, but enterprising over-
clockers have cranked this bad boy to 2.4GHz and beyond.ATHLON 64 VENICE 3800+ Out of the box it runs at just 2.4GHz,
but up the voltage and you’ll be fl ying high at 2.8GHz in no time!