Bus Powered HDD vs AC Plugged Drives on iMac

[peeaanuut]

So I have a few external HDDs right now. All are in E-Sata/USB2 enclosures, so I am abviously using USB2 with my iMac. Well, I have an opportunity to pick up some bus powered USB3/FW800 enclosures for 2.5" drives at a super cheap price. My question is, if I run 3 or 4 of these all on bus power, will it overload what power the imac can send to each port? I know its plugged into the wall, but there seems like there might be power delivery issues.

My goal is to slim down what is on my desk AND remove things that are physically plugged into the wall.

Thoughts?

 

[SDAVE]

Shouldn't be a problem. Each port has enough juice to power a drive.

If you run a USB hub you might run into issues. There are USB hubs that have power adapters too.

However, 2-3 drives will not be an issue. What's cool about FW800 is that it can be daisy chained, so you just run 1 FW800 cable from the iMac and then daisy chain the other drives.

I would go with FW800, way faster and more stable...less CPU strain too.

 

[peeaanuut]

yeah, I already have 1 FW800 drive and love it and going to FW800 was the goal for sure. I just didnt know if the bus would overload if I strung 3 or more of them together. The drives are 2.5" drives so not much power anyways but i cant be frying my baby. Also I figured with the enclosures having USB3 they could dbl up for when I get my new rMBP and beyond.

So, here is a scenerio.

If I run drives 1 and 2 in the chain as bus powered and then 3 as AC than then 4 as bus, would 4 feed off the AC from 3 and therefor releave any strain I am putting on the iMac after the first 2? Does that make sense?