Hi - I would take the Seasonic X series anyday over the other two.
But, if you're willing to pay the $129 plus shipping for the x-650,
then you should get the X-750 for $99.99 & free shipping, limited time of course.

http://e.newegg.com/servlet/cc6?gLmkQSBRTQUV2w5zg24xG602aebvdQvG2VaVSBVXLX

Tom

ooops - sorry - deal expired, was for 1 day only.
 


Hi again - If you'll entertain anything other than those three, plz consider this Corsair:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139020&name=Power-Supplies

promo expires 10/26

Tom
 


No - I don't with the ss 660 - but it's replacing the x650 which I have and works like a charm.
Really nice the fan only runs when needed.
If I'm purch a PSU for myself it'll be a Seasonic, even tho there a several other top shelf brands.

Tom