I want to use 2 GTX 460s in SLI. My question is if I need to worry about using this power supply to power up 2 GTX 460s. I'm aware that my power supply only has two six pin connectors, so I plan on using 6 pin adapters to power the second one. From what I've read online, I can expect to use around 400-470 watts under load with my PC if I were to use 2 GTX 460s, I'm just not entirely sure how this power is distributed. I do not plan on doing any overclocking. Would I be risking my PC if I were to use these cards? I don't really want to spend $100 on a new power supply.
No, that will not be enough to run both cards. Peak will be closer to 500/525 watts and your processor used 130 watts without any overclocking. Plus you will need voltage for ram w/ southbridge chipset and cooling fans, audio. usb and all that stuff. You would be better off with an Antec CP-850 850W Continuous Power CPX SLI Certified CrossFire Ready 80 PLUS Certified Modular Active PFC "compatible with Core i7" Power Supply for $120. I know it's more than you were planning on but you need to get something that WILL work.
it can probably deliver the 390W (from the psu) experienced in Crysis. But its likely to struggle if loads approach the 470W (from the psu) if you then add maxing the cpu at the same time. Unless its an Antec Basiq like the one Hardware Secrets pulled 640W from.
Whether its dangerous or not depends on how the Antec fails, if it fails, when it fails. It should just shut down if loads exceed what it can actually provide despite its rating. But its an entry-level psu.