ExtremeTech tested one of Samsung's hybrid hard drives last week. This is a HDD with some integrated flash memory to improve performance and lower power consumption:
So far, so good. But as applications demand more memory, not everyone will be equipping their laptops with 2GB or more. So what if the hard drive itself had a dedicated, persistent cache? When the system needed data from the drive, that flash memory cache could serve up the requested data, with no need to spin up the drive. Plus, read transfer rates would be higher than data read from a typical 2.5-inch platter. Even returning from hibernation would be faster, so the thinking goes, and consume less power.
That, in essence, is a hybrid hard drive: You take a standard hard drive with rotating platters and add 256MB or more of flash memory. That flash cache is persistent since it's flash memory. It all sounds very good in theory.
Check it out over here. Overall the reviewer wasn't impressed by the Spinpoint MH80 Hybrid HDD. The slow performance, higher power consumption under load and high price lead to a score of only four out of ten.