Ok. So as you all know I've been making a fairly nice build based around an EVGA 680i Motherboard.
Well it's finally running and now I'm looking into putting that SLI capability to good use but I'm not 100 percent sure of my power calculations.

The system currently has:

Windows 7 32-bit (Currently running late 2009 NVIDIA drivers including the 15.00 series nForce drivers)
Intel Core2Duo E7200 (I plan to upgrade that to a E8600, seeing as how there both 65 watt there shouldn't be an appreciable difference)
EVGA NVIDIA GeForce 9800GTX+ (This is the 55nm die shrink which has a TDP of 150 watts and only requires one PCI-E 6 pin)
3GB of assorted DDR2 (Currently running at 400MHZ, i plan to replace it with a NVIDIA SLI Certified EPP memory kit from OCZ that supports the 800MHZ PC2-6400 standard)
2 Hard Drives (1 2.5 inch laptop hard drive made by samsung, and a second full size WD Caviar Blue 500GB)
1 DVD-RW Super-Multidrive
2 Case Fans (1 standard, one LED)

Now my current power supply is the Antec Earthwatts EA500D. According to most era reviews the max the power supply will provide is 450 watts on the 12v rails @ 40AMPs while retaining 80+ efficiency.

My power calculations are as such

1x65 watts (Processor) = 65 watts
2x150 watts (Graphics) = 365 watts
3x10 watts (Drives) = 395 watts
2x5 watts (Fans) = 405 watts
1x30 watts (Anything not accounted for by other categorys) = 435 watts?

Have i overlooked anything or made any series errors in my calculations? Judging by this, that SLI setup would be perfectly sane. I just feel like i may be a bit too close to the edge of the performance envelop.