Replace the optical drive with a hard drive caddy. Put the SSD in the original hdd bay and a mechanical hdd in the caddy. Sometimes slimy manufacturers limit optical bay SATA to 1.5Gbps so you don't want to put your SSD in there, the original hdd bay is guaranteed to be the faster of the two if there is any difference. Best of both worlds. If you still need one, external optical drives can be had for around $30.
Based on the review on Notebookcheck.net it seems that the X70 already has a 256GB SSD and a spare drive bay. So none of the replies so far make any sense, other than Chrispy_'s recommendation of the Momentus XT. I've got a Lenovo notebook that originally came with one (swapped it for a 120GB SSD, didn't need the space and wanted the speed) and they're about as good as it gets for 2.5" mass storage, like if you wanted it for games.
I do not understand what I do. For what I want to do, I do not do. But what I hate, I do.
derFunkenstein wrote:Based on the review on Notebookcheck.net it seems that the X70 already has a 256GB SSD and a spare drive bay. So none of the replies so far make any sense...
That's only because none of the rest of us bothered to read the specs on the X70 (over-achiever). Given this new info, I don't think the additional cost of the Momentus XT is really necessary for data storage (it generally matches performance of 7200rpm drives). For a primary system drive, sure, but not here.
If you've already got a SSD in there, check prices and get a 5400 rpm hdd. In general, 5400 rpm hdds will: be quieter than 7200rpm models, use less power than 7200 rpm models, extend into higher capacity points, and should cost less than 7200 rpm models.
I would find the XT useful if I had Steam installed, or something other than movies/music/photos on the second drive.
The XT (or any hybrid for that matter) has the benefit of 7200RPM performance with only 5400RPM noise and power consumtion, but also if you have to install an infrequently-used application (or want a Steam game installed that you only play occasionally) it will still run at near-SSD speeds on the XT after it's first couple of launches.
If the OP only wants cheap, he'd have said just "good cost/value" but he definitely said he wanted speed as well. It's only my opinion, but I'm starting to feel that the newest hybrids are really starting to patch up the IO problems of 2.5" mechanical drives. The problem with mechanical storage isn't the difference between 5400RPM's 70MB/s and 7200RPM's 95MB/s sequential rates, it's the fact that without NAND to buffer the small-file reads, you sometimes only get 200KB/s out of a 2.5" drive. With 20MB of small files for application x, that's a couple of minutes of tedious waiting that could be over in a few seconds on an SSHD.
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