Hardware Reference
In-Depth Information
XMP
eXtreme Memory Profile
(XMP) is an Intel-developed exten-
sion to JEDEC memory standards that allows premium DDR3
memory to run at timings faster than standard JEDEC values.
XMP essentially automates the formerly manual process of
tweaking memory to run faster than its nominal speed. Using
XMP requires XMP support in both the system BIOS and the
memory modules themselves.
yield higher memory performance at the risk of compromising
system stability. Gamers, overclockers, and other performance
enthusiasts often enable XMP on their systems for the minor
performance advantage it provides.
The Intel DX58SO and the Crucial Ballistix memory modules we
used in our extreme system both support XMP, but by default
run with standard memory settings. If you want to enable XMP,
run BIOS Setup, choose the Enthusiast or Extreme profile, ignore
all the Intel warnings, save the settings, and restart the system.
A standard memory module includes a
Serial Presence Detect
(SPD) ROM, from which the system BIOS can read recom-
mended timings for that module. These standard timings are
generally quite conservative, and therefore provide slower (but
safer) memory performance data than the module is actually
capable of providing. XMP-enabled memory modules use an
unallocated area in the SPD ROM to store additional memory
timing settings—designated “enthusiast” and “extreme”—that
In case you're curious, we run our extreme system with standard
JEDEC timings. The small performance advantage of XMP is
more than offset by the risk of reduced system stability, at least
to our way of thinking.
VideoAdapter
ASUS EAH4350 SILENT/DI/512MD2(LP)
(
http://www.asus.com
)
Choosing a video adapter (or adapters) for an extreme system can be anything
from very simple to very complicated indeed. If 3D graphics performance is
unimportant—as it is for our extreme system—you can simply use integrated
video or install an inexpensive video adapter. If 3D graphics performance is
critical—as it is for a gaming system—you'll have some decisions and trade-
offs to make.
Nearly all desktop 3D graphics adapters are based on a chipset (
graphics pro-
cessor unit
, or GPU) from one of two companies, ATI or NVIDIA. Each of these
companies produces many chipsets in a wide range of prices and performance
levels. Numerous companies produce video adapters based on these chipsets,
at prices ranging from $20 or so up to $750 or more. As you might expect,
more expensive cards are faster. At the low and middle ranges, price correlates
pretty well with performance. For example, an $80 video adapter is much fast-
er than a $40 adapter, and a $160 adapter is much faster than the $80 adapter.
Above $150 or $200, you rapidly enter the realm of decreasing returns. A $300
adapter may be only 25% faster than a $150 adapter, and a $600 adapter may
be only 10% faster than a $300 adapter. Even a $75 adapter is fast enough
to play all but the most recent graphics-intensive games at reasonable frame
rates, although you may have to use something less than maximum resolution
and make other tweaks to get smooth game play.
