Over the past few years Seagate has been trying to perfect a way to get the best of both storage worlds by combining an SSD as a semi-permanent cache for a large platter based hard drive.  The new Seagate Momentus XT is the third generation of this series, a 750GB HDD with a 8GB SLC SSD available to cache frequently used files and are calling it FAST (Flash-Assisted Storage Technology).  Legit Reviews investigated their performance claims, after repeatedly using the drive to fill the cache as this drive will perform exactly like the platter based drive it is until that cache has moved frequently accessed or slow to load files into the flash memory.  It did seem to reduce boot times and program loading to almost SSD levels, though it does not effect infrequently used programs.  It was significantly less expensive than an SSD so if you tend to do similar tasks on your PC every day and need the large storage space this drive might just be for you.

"Overall, we’d certainly recommend the Momentus XT and frankly wouldn’t go back to a plain old hard drive unless we were forced to. The expediency of boot and application load times are something that, once you get used to it, you can’t seem to live without. Keep in mind that it may take two or three times for the Adaptive Memory Technology to decide that it should be cached and speed things up. On the down side, every operation is not SSD fast, especially if you’re performing it for the first time…"

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