An analyst for Objective Analysis claims that PCIe and standard interface SSDs technology will work together for a long time.

Many others claim that SSDs will replace PCIe as soon as the price drops but Jim Handy told Digitimes there is a lot of life in the old hard-drives yet. He said that NAND-on-the-motherboard is a technology that will happen in time, and when it does it will certainly reduce the penetration of SSDs into PCs, but it is not presently clear when that will happen.

Handy said that this is a miniature version of the way that SSDs are being used in the enterprise with a small, cheap amount of solid state storage for everything that needs to be fast, and inexpensive HDD capacity for everything else. SSDs make most sense in systems with numerous HDDs where fast drives are used to store some data, but the vast majority of data is stored in inexpensive capacity HDDs. He said that SSDs are a very economical alternative to fast HDDs in these systems and often provide higher performance than the enterprise HDDs they replace.

He added that PCIe is a much faster way to communicate with the CPU than are standard disk interfaces. HBAs and RAID controllers already take advantage of this and are in widespread use. A PCIe SSD is not really replacing an enterprise HDD as much as it is replacing an HBA or RAID controller with a number of HDDs. PCIe SSDs will continue to be very popular but will not displace SSDs that have conventional HDD interfaces. Both PCIe and standard interface SSDs should coexist for a very long time.