700W enough juice?

It should have enough power for that and the SLI.

That's a surprising answer, I figured those HDDs would suck up a lot of juice. Perhaps not so much then?

No more than 10W each.

They do draw power from the 5V rail however. I'm not sure how many Watts that PSU has on the 5V rail, but you might start to have issues. The answer of course is to just get a few bigger drives and move the smaller ones over. That or put them in USB cases and only plug them in when needed.

You've got plenty of power overall. I'm just worried about that 5V rail.

There's 5x28= 140W on the +5V rail. But I could have sworn that it was powered by the +12V rail.

Actually, my bad, we're both right:
http://www.overclock.net/power-supplies/675488-what-rai...

Ok, while looking into my PSU specs to find 5V stuff (only thing I could find said max load - 28A for the 5V stuff), I found a really cool utility for calculating needed power.
http://www.thermaltake.outervision.com/Power
and putting in all my specs it looks to be in the 750W range recommendation.
I suspect their estimates err on the high side to be safe so in the end I probably have just enough for now. Esp if I take out a couple drives which won't be a prob after I get finished with all my raid rebuilds and data swaps.

Also looks like they rate the HDDs at about 20 watts per 7200 drive

I think HDD's take power from the 5V and 12V rails. 5V for the electronics and 12V for the mechanical (platter spin and head movements) elements.
Here is a THG chart with some current HDD power requirements.

Drives get power from both rails. I'm not sure how much is drawn from the 5V rail, but seeing as he has 12(!) then he might be hitting the top end. In addition, seeing as the move has been to the 12V rail, that leaves less and less power for the 3.3v and 5v rails. 140W seems to be a correct amount of power, but realize as his 12V rail use goes up, less power will be available for the other rails. Modern PSUs can output very close to 100% of its power on the 12V. I don't think his rig will do this, but even 140W will start to have issues.

As you said, about 10W each. 10W x 12 = 120W. How close are we to maxing out this 5V rail? Much to close I would argue. I still think the best course of action would be to start getting those drives out. And if the power problem doesn't do it for you, just think of the heat caused by 12 drives.

I'd go with the 10W figure Lex. First, the only time your going to cause the most strain on your PSU is when you turn the machine on. Drives only consume max power when they are in use. Just sitting there idle isn't going to cause them to draw a lot of power. I think their standby amount is around 5-7W. Actual use is around 10-15W. The power calculators often use higher then real numbers. Think about it. You went to a thermaltake website to get your figure. Do they want to sell you a 500W PSU or an 850W?

Your Thermaltake Toughpower 700W PSU is probably more powerful than the 'standard generic 750W PSU recommendation' that the PSU supply calculator serves up.
The PSU calculator recommends a PSU size that would be comfortable running the items you plugged into the form.

Well, it'd be nice to get the drives out, the raid card boot up time is enough to bug me enough as is, nevermind heat, but I can't afford a slick NAS like I'd really want so at minimum 8 of the HDDS are stuck in there for now. (4x WD 750GB @ 7200 and then 4x Samsung 2TB @5400)

Once I get my SSD one 500GB drive I'm using as my temp os drive will be out the window and once my data is all set up on the raids the way I want (its taking its sweet time) I can probably go ahead and toss the additional drives. Leaving me with 8 HHDs and an SSD. With what I've gathered, I feel that my PSU will be adequate for the time.

Thanks for the assistance fellas.

My bad. I read it as four hard drives total. Yeah you'll want a bit more power.