here's what i did in your situation:
1 main 256ssd and 2 external 5400 usb backup drives (2.5" each). i have lion and adobe apps installed on the ssd, and projects are loaded off of the external drives (both are clones of each other). i'm planning on switching to raid 1 mirrored drives at some point as it would be easier to work with compared to my current setup.
That isn't an option.
The whole point of the HD upgrade Is not to carry around an external one.
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My battery life appears to be the same. It's probably slightly lower than with the stock. When I'm not running anything I'll get a full 7 hours+. I currently have a few applications running with several Firefox tabs open and I have 3:45 remaining with 69% battery.
Supposedly the 7200's are faster than 5400's but I haven't noticed a thing. Unless you have your face to your laptop or you're in some setting with complete silence, you won't notice the sound, but that's the same with 5400's. Most people who are really sensitive about the sound issue say that there's not really much of a difference and they often don't notice.
I never had the old XT so I can't give you an experience on the different between the 3Gb/s and the 6Gb/s. I read about a dozen reviews when looking into this drive before buying and almost all of them said that there was just a considerable difference in every aspect of the newer model.
Chances are Seagate will release something new towards the end of 2012 or sometime in 2013 but the price-tag on it will be much higher. The price of the current 750GB will probably go down when a newer model is released but it's really only speculation on when something will come out.
Thanks for clearing it out.
Ill be going with the 750gb xt!
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5400 vs 7200 isn't so cut and dried.
Spinning disk read/write speed decreases as you move from the beginning of the disk to the end, and this drop off increases dramatically as you go beyond 50% capacity.
So with that in mind - a 5400rpm drive that is using only half its capacity may be faster than a 7200rpm drive that is 80% full - for the hot data that you are actively working on which will be at the end of the consumed space.
For the best speed, buy at least 2x as much space as you need, and then if you can afford/find a drive that is higher rpm of that size, go for that.
Conversely, if your option is only a 750gb 5400rpm or 500gb 7200rpm (as mine was), work out how much you can keep OFF your disk. If you're going to need say 400gb of space, the 750gb drive may well be faster for the "hot" data you are currently working on (which being new data, will be at the end of the disk).
see here:
http://macperformanceguide.com/Storage-WhyYouNeedMoreThanYouNeed.html
and
http://macperformanceguide.com/Storage-BiggerIsBetter.html
I suspect that if you "need" 400-500gb of space, a 750gb drive will be faster, even if it is only 5400rpm, vs a 500gb 7200rpm drive. If you can get a 1tb 5400rpm, even better.
Al other things being equal (same size drives) - 7200 rpm will be faster, particularly when multitasking, swapping to disk, etc. It can simply seek to different locations on the disk faster. It just depends if you're willing to pay the extra for the faster drive.
With all that in mind, for 400-500gb of data i'd be looking at the Seagate Momentus XT 750gb hybrid, if you can afford it.
Ill be doing multitasking so the 7200 Will fit me well.
You guys are so helpull!
I am gracious