Datasheet

Calculating the WEI
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TABLE 1-1: WEI CAPS FOR THE MEMORY (RAM) COMPONENT
If You Have This Much Memory
(excluding memory reserved Your Memory Score
for graphics) Gets Cut Off At
256MB 2.0
512MB 2.9
768MB 3.9
Less than 1.5GB 4.5
1.5GB or more Score isn’t capped
Graphics Component
The Graphics Component WinSAT score determines
whether Vista will try to run the Aero Glass interface
automatically. It’s a two-dimensional video-centric
measurement. WinSAT runs the following three
video bandwidth benchmarks, mashes the results
together, and comes up with a score between 1.0
and 5.9:
 WinSAT simulates the Desktop Windows
Manager — the program that controls the Aero
Glass interface — at work, calculating the num-
ber of frames per second DWM.exe can push
onto the desktop.
 It runs a Video Decoder test and measures how
long your PC takes to display video.
 Finally, WinSAT measures video memory band-
width in megabytes per second.
The graphics component score is a two-dimensional
kind of test, with emphasis on playing video (includ-
ing movies, TV, and the like) and the specific needs
of Vista’s Aero Glass interface.
Every recent graphics card supports the DirectX9
specification, which makes it faster for programs to
interact with the screen, and WDDM, the Windows
Display Driver Model, which provides a uniform way
for programs to show things on the screen. If your
graphics card doesn’t have a DirectX9-compliant
driver, WinSAT sets your Graphics Component score
to 1.0. If it doesn’t have WDDM, the highest score
you can get is 1.9.
Gaming Graphics Component
More than anything else, the Gaming Graphics
Component measures your video card’s ability to
handle 3D graphics. Internally, this benchmark is
called the D3DScore — D3D being geek shorthand
for Direct3D, Microsoft’s proprietary set of com-
mands for high-performance, three-dimensional pic-
ture rendering. WinSAT runs three different Direct3D
benchmark tests:
 An alpha blending test that determines how
quickly your graphics card can blend together
two colors in a standard, semitransparent way.
 A straightforward calculation test that assesses
the graphic card’s computing power when work-
ing with shades.
 A shader texture test that measures the graphic
card’s ability to load textures.
Again, the three raw scores go into a blender, and
the result is a score between 1.0 and 5.9.
The score can get clipped. It’s set to 1.0 if the graph-
ics card doesn’t support the older Direct3D version
9.0 standard. If the graphics card can’t handle the
Pixel Shader 3.0 spec (
en.wikipedia.org/wiki/
Pixel_shader
), the score maxes out at 4.9, no mat-
ter how fast the graphics card might be.
Any card that supports Direct3D 9.0, DirectX9, and
WDDM (see the preceding section) receives at least
a 2.0.
Primary Hard Disk Component
Surprisingly, the Primary Hard Disk Component
doesn’t look at the size of your hard disk, how much
room is left, its fragmentation, caching, seek time,
rotational latency, or anything else that you learned
in hard disk school. Confronted by ultrasmart hard
drives, caches, buffering policies, hardware optimiza-
tions, look-ahead, write-behind, and all sorts of con-
founding capabilities of hard drives and their drivers,
Microsoft basically threw up its hands and gave up on
any attempt to measure all-around disk performance.
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