My pleasure. Just as a side note, one thing you'll have to consider, is how many PCI-E 6pin connectors your PSU have.
Now, relative to the manufacturers (ASUS, MSI, GIGABYTE, etc) the design changes. Some requires two PCI-E, some requires only one.
The reason I mention it, is this:
(this is a hypothetical scenario)
You have 970 SLI with a design that requires 2x6pin PCIE connectors in each individual card, totaling 4x6pin PCIE for doing SLI.
The problem is, that most under 1000W PSU's usually have at most 2x6(+2)pin PCIE (where you manually can remove 2x2pin to make it 2x6pin) or normally 1x6(+2)pin PCIE.
That means you are forced to use adapters. The problem with adapters (molex to PCIE) is that the effect is inferior to that of PCIE cables directly from the PSU. So, if you have a PSU at the bare minimum (650ishW) and only 1x6pin PCIE, then it is possible that you can't do SLI, because your adapters do not deliver enough effect. If it specifically had 4x6pin PCIE, then even a low-to-mid quality 650W, should be able to do SLI.
So very important in my opinion.