If you have $500 and a free PCI-E x4 2.0 slot then OCZ has a rather unique product you could try out.  This new RevoDrive Hybrid is a 100GB PCIe SSD card with a low power 2.5" Toshiba 1TB HDD spinning at 5400RPM.  You could think of it as similar to an Agility 3 120GB, though in this case it is acting as a very large cache for a HDD using OCZ’s proprietary Virtualized Controller Architecture 2.0.  Performance-wise this odd looking beast surprised Hardware Canucks, beating the hybrid drive from Seagate as well as the Intel SRT that they tested against, but they caution prospective buyers about some sacrifices that had to be made by OCZ.  These drives are not quite plug and play, they require software to be installed in order to function properly and it turns out that the software is quite CPU intensive.  Read through the article and see if the sacrifices are worth the gains for your system.

"Searches for affordable high capacity SSDs usually come up blank so several manufacturers have begun releasing hybrid solutions which combine the performance of an SSD with the storage space of the hard drive. OCZ’s RevoDrive Hybrid is the latest to take on this challenge by combining a 100GB SSD with a 2.5" 1TB HDD. This isn’t exactly a match made in heaven but the benefits are tangible."

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