The GTX 460 requires two 6-pin PCIe power connectors. That PSU provides two 6-pin PCIe power connectors, which isn't enough for SLI 460s. You could use adapters, but that's not a good solution, especially with a PSU that would already be pushed hard. You need to invest in a new PSU if you want to go SLI.
I'd get a single new graphics card instead, like a GTX 660 or Radeon HD 7870.
Also, the AMD FX 6100 is a bad CPU for gaming. At least get the newer FX 6300.
If you're buying off Newegg, there are a couple other good options to consider. The Corsair TX V2 750W is actually a little cheaper than the XFX with the rebates factored in. And there's an OCZ Fatal1ty 750W if you'd like a modular PSU.
Thank you for your replies ! Prototype18. Great Review, i read it all. I'm posting its conclusions below in case anyone else has this question in the future. The psu its under 5 yr warranty, ( which is how long i had the unit ). It has gone through 1 upgrade already, and can handle my next upgrade if i don't buy an additional 460gtx. But it seems if i want to run sli, i would need higher wattage. I would also like to OC, so just to be on the safe side hehe. Thanks again!
Hardware Secrets Golden Award
This power supply is simply unbelievable: even though it is labeled as a 550 W unit it could deliver 650 W at 50º C. What an animal! Several power supplies on the market aren’t able to deliver its rated power under real-world conditions – namely a room temperature above 40º C – and this power supply could not only do that but deliver 100 W more power! Costing around USD 110 this product presents one of the best cost/benefit ratios on the market, as you will be paying for a 550 W unit but actually buying a 650 W unit. It deservers nothing less than our “Golden Award” seal.
During our tests it provided an efficiency between 83% and 88%, which is outstanding, as it will allow you to save some money on your electricity bill compared to units with efficiency below 80%.
Feature-wise this power supply uses a modular cabling system. We like systems like this as you can remove all the cables you are not going to use, helping the computer internal airflow. Even though it uses a traditional 80 mm fan on its rear, this fan was very quiet when the power supply was working at a light load. As we mentioned, the power supply fan speed changes depending on the unit’s internal temperature.
Another great feature about this power supply is its warranty: 5 years. This only shows the commitment of the manufacturer that you won't have any problem with this unit.
With two auxiliary PCI Express power connectors for your SLI or CrossFire system and one EPS12V connector, which is used by some high-end motherboards, this power supply should be enough even for some high-end users. Of course If you go with SLI or CrossFire with the most high-end video cards available today you will need a power supply with a higher wattage, like 850 W.