HDMI, DVI, VGA power draw from graphics card
HDMI DVI VGA displays will each have it's own power supply, but does one draw more or less power from the graphics card? Thanks.
The digital interfaces all use the same LVDS transmission coding and will use a similar amount of power for any given bitrate - their transceivers are all the same, which is why you see different GPUs offering different mix of DP, DVI and HDMI ports.
VGA on the other hand requires analog circuitry which operates at higher voltages and DACs (along with the ADCs required at the monitor's end) also consume a fair amount of power due to their analog nature.
siveshen said:display types are not really a factor when it comes to power consumption in a pc though i suspect that vga could use slightly more power than Dvi and possibly Hdmi will use less power than Dvi.
VGA will use A LOT more power than DVI/HDMI since AD/DA converters are inherently highly inefficient: a bunch of resistor or current source networks and analog amplifiers. A digital link uses a few hundred milliwatts while an analog one will use two or three watts, that's a factor of about 10X.
DVI and HDMI use exactly the same video signaling format, which means no meaningful difference beyond connector parasitics.
Compared to the 10-15W used by the GPU to simply scan the VRAM to refresh monitors though, the 300mW or so on digital links is insignificant.