While Intel and AMD have moved aggressively towards reducing
the amount of power processors consume, nVIDIA and AMD have largely neglected the
concerns os energy efficiency. High end videocards can often draw more power than a CPU in a computer.
With the AMD R600 core built on TSMC's 80nm technology, you know
this GPU will use up a lot of power.
To get an idea at
how much power the Diamond Viper Radeon HD 2900XT 1GB consumes, consider this. The
PCI Express x16 slot provides up to 75W power, and each additional six
pin VGA power connector a further 75W. The new eight pin
PCI Express power connector can deliver up to 225W of power.
While we have no way of directly measuring how much
power the Viper Radeon HD 2900XT draws, PCSTATS can measure total system power draw and compare
that same basic installation to a couple different videocards. That will give you a
rough idea of how much power the Radeon HD 2900XT is drawing under idle
and loaded states.
For PCSTATS total system power draw tests, the PC will consist of the following hardware: AMD
Athlon64 FX-62, Asus M2-CROSSHAIR motherboard (for nVIDIA videocards) and an ECS
KA3 MVP Extreme motherboard (for the Diamond videocard), a reference Athlon64
FX-62 cooler, 2GB of Corsair Twin2X2048-6400C3 memory, a 74GB
WD Raptor hard drive, an 8x Gigabyte DVD writer and a floppy drive. The power supply used
here is the A-PFC compliant Seasonic S12-600W.
The videocards that will be tested
against the Diamond Viper Radeon HD 2900XT 1GB come from both the nVIDIA and
ATi camps. Representing nVIDIA are the MSI NX8800GTX-T2D768E-HD (GeForce 8800GTX), Foxconn
FV-N88SMCD2-ONOC (GeForce 8800GTS 320MB), MSI NX7950GX2-T2D1GE (GeForce 7950GX2), a MSI NX7900GTX-T2D512E
(GeForce 7900GTX) and a Gigabyte GV-NX76T256D-RH
(GeForce 7600GT) videocard. Representing ATI/AMD are an Asus X1900XTX 2DHTV/512M/A (Radeon X1900 XTX) and an Asus EAX1950PRO/HTDP/256M/A
(Radeon X1950 Pro) videocard.
[ *This figure represents total
system power consumption in Watts, either with the system at idle, or the peak
value recorded while running 3DMark06. ]
one Diamond Viper Radeon HD 2900XT videocard draws 178W, about 18W less
than the MSI NX8800GTX-T2D768E-HD. Even when a single Radeon HD
2900XT is overclocked, it still draws less than one Geforce 8800GTX.
Energy consumption jumps a lot when the videocards are under
The MSI NX8800GTX-T2D768E-HD draws more power (345W) than a
Diamond Viper Radeon HD 2900XT (337W). With one Diamond HD 2900XT
overclocked, power consumption rises slightly to 346W. With two Radeon HD
2900XT's running in Crossfire, total system power consumption jumps considerably
to 549W. Overclocking the Crossfire videocards bumps that figure up to an
astounding 573W of power!
Wow, I never thought we
would see power levels reach such levels... but there you have it, an overclocked Crossfire pair of Diamond Viper Radeon HD
2900XT's pushes total system power draw to 573W! Remember, Diamond recommend using a minimum 750W
power supply with these videocards.
Overclocking is up next, but first PCSTATS has H.264 Blue Ray HD content