For today's article we make use of GeForce GTX 970 cards and though you might just have read our reference article.
Each GeForce GTX 970 will come with 4 GB of graphics memory, that's definitely enough if you are a hardcore gamer with a monitor resolution of 1920x1200 and upwards to Ultra HD. If you plan to game on triple monitors then actually 4 GB starts to make a bit more sense as this will definitely help you out in the uber high resolutions and with hefty AA combinations.
The GeForce GTX 970 has a maximum power consumption of 165 Watts, you'll need to power the card with two PCIe PEG leads from your power supply per card. We recommend a 700~800 W power supply to start with two card. We need a little extra Wattage for efficiency, but you also want a little reserve if you plan to overclock processor or the GPUs. Extra voltage can really eat away in your power consumption fast.
The GeForce GTX 970/980 PCB itself is based on a 4-phase power design for the GPU with an added phase for the memory subsystem. The card is PCIe Gen 3.0 compatible. Going from PCIe Gen 2 to Gen 3 doubles the bandwidth available to the add-on cards installed, from 500MB/s per lane to 1GB/s per lane. Like any high-end GeForce graphics card, Nvidia will allow you to opt for the multi-GPU road as you may pair two or three cards in one PC -- heck even four if you are up for a daunting task of course.