Videocard Power Consumption Measurements

For a while now, the video card has been the biggest consumer of power in high-end computer systems. The burgeoning market for 650Watt and up power supply units has been driven primarily by this fact, and the trend shows no sign of ending (though the newest generations of high end cards from ATI and nVidia are a little more efficient than their predecessors of a couple of years ago).

As you've probably guessed, the Palit HD4870X2 videocard is not going to be an exception to this phenomenon. With its dual HD4870 GPUs, its going to need power, and lots of it to run correctly.

ATI recommends a minimum of 600 watts for the HD4870X2, we recommend Westinghouse's new personal iNuclear 220 Desktop Power Plant. The device is about the size of a toaster oven, but the 5 gram enriched uranium power source is capable of delivering 2.2megaWatts of electricity by way of the hermetically sealed regenerative turbine system. (ie. no mess, no need for a coolant cooling pond in your back yard). ;-)

The Radeon HD 4870 X2 uses two PCI-express power connectors, an eight pin and a six-pin. The 6-pin connectors, like the PCI-Express x16 slot itself, deliver up to 75W of power. The 8-pin can deliver a whopping 225W (though the card has been designed to work with 2 6-pin connectors as well). This means that we're looking at power consumption numbers up to about 200W! We'll get a clearer look at how much actual power this card will eat in a moment.

Videocard Power Draw Comparisons

Here's how the Palit Radeon HD 4870 X2 videocard stacks up in real life against a couple different cards We have no way of directly measuring video card power draw, so PCSTATS will measure total system power draw and compare that in 3D loaded (max value recorded in 3DMark06) and idle states (at Windows desktop). The power supply used in each test is an A-PFC compliant PC Power and Cooling 750W model.

Videocard Power Consumption (Total System Power Draw) Idle at Desktop Watts Ranking Palit HD4870 X2 2GB 177 Asus EAH3870 X2 1GB TOP/G/3DHTI/1G/A 153 MSI R3870X2-T2D1G-OC 165 ATI Radeon HD3870 X2 1GB in Crossfire 222 Diamond Viper Radeon HD 2900XT in CrossFire 195 Asus EAH4850 HTDI/512M 120 Asus EAX1900XTX 2DHTV/512M/A 160 Asus EAX1950PRO/HTDP/256M/A 150 nVidia Geforce 9600GTs in SLI 166 Asus EN9600GT Top/HTDI/512M 152 Palit Geforce 9600GT 512 151 MSI NX8800GTX-T2D768E 196 MSI NX7950GX2-T2D1GE 183 MSI NX7900GTX-T2D512E 165 Gigabyte GV-NX76T256D-RH 140 3D Loaded: Watts Ranking Palit HD4870 X2 2GB 421 Asus EAH3870 X2 1GB TOP/G/3DHTI/1G/A 390 MSI R3870X2-T2D1G-OC 330 ATI Radeon HD3870 X2 1GB in Crossfire 610 Diamond Viper Radeon HD 2900XT in CrossFire 549 Asus EAH4850 HTDI/512M 202 Asus EAX1900XTX 2DHTV/512M/A 333 Asus EAX1950PRO/HTDP/256M/A 252 nVidia Geforce 9600GTs in SLI 313 Asus EN9600GT Top/HTDI/512M 220 Palit Geforce 9600GT 512 221 MSI NX8800GTX-T2D768E 345 MSI NX7950GX2-T2D1GE 315 MSI NX7900GTX-T2D512E 277 Gigabyte GV-NX76T256D-RH 213 (OC) 3D Loaded: Watts Ranking Palit HD4870 X2 2GB 426 MSI R3870X2-T2D1G-OC 339 ATI Radeon HD3870 X2 1GB in Crossfire 630 Asus EAH4850 HTDI/512M 231

At idle, the Palit HD 4870 X2 videocard and test system draws approximately 177W. Energy consumption jumps a lot when the video cards are stressed under a 3D gaming load in 3DMark06. In this case, the total system power draw for the Palit HD 4870 X2 test platform rises to a peak of about 421W. That's a change of about 245W when this dual card is working at its peak. Keep in mind that some of this additional power is being drawn by the CPU and memory, but it looks like each GPU is approaching 100W of power burn at least.

Consider this as a general guideline, since power consumption will vary with the demands and components of individual systems, but it's fairly obvious from our numbers that the recommended 600Watts of PSU power is a pretty accurate mark, once you add in the variables like additional drives and other power draining peripherals.

Now let's have a look at how Palit's dual-core beast overclocks.