What parts do I need?
The most obvious thing that you are going to need is two PCI Express graphics card which are of the same make and model - SLI is not supported on AGP graphics cards. The lowest end SLI capable card is the GeForce 6600GT which has quickly become known for its great bang for buck. From there you move into the 6800 series which consists of the GeForce 6800/6800GT and the biggest bad boys around the GeForce 6800 Ultra's which we have here today. Keep in mind later in the year ATI is expected to deliver an answer to nVidia's SLI with AMR (ATI Multi Rendering) but details on this technology are scarce at the moment.
The most common SLI capable motherboard floating around at the moment is the ASUS A8N-SLI which while it does have a few little issues has quickly become an excellent fixture to any enthusiast's computers. With good availability on the motherboard and its price, it really is a great motherboard and has really proved itself to us here at TweakTown considering the amount of stress we have put it under over the past few weeks trialing out SLI for all it's worth. Other SLI boards are starting to become available from companies such as MSI and DFI but ASUS is clearly at the forefront with an SLI solution out way in front of everyone else.
nVidia recommend a quality power supply which is capable of delivering at least 500 watts of power. We have been using an Antec 450 watt power supply though for the last few weeks without any issues. If you are looking at setting up an SLI system, don't be stingy when it comes to buying the power supply. With two graphics cards, come great heat - so case cooling is also essential part of the setup, especially if you intend on overclocking the cards.
While these components are extremely important the biggest thing most people need to enter the SLI market is MONEY. There is no denying that jumping on the SLI bandwagon is expensive - according to our price comparison website for a base SLI system at the time of publishing you'll be looking at around $400 US for the two GeForce 6600GT's, around $250 US for the ASUS A8N-SLI motherboard and extra for all the other parts not forgetting the beefy high quality power supply. This adds up to $650 US just for the baseline SLI parts and a lot more for the 6800 Ultra version of the setup.
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