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I've had a 2900, and got an X2 now, it's only about an inch longer, one thing you need to watch out for is what motherboard you have, where the SATA ports are located, and how many you've got in use. I've got a P5K deluxe, and all my SATAs are in use. My X2 wouldn't fit because of the SATA cables so I had to cut the plastic/rubber grips at the end of my SATA cables so they can bend more, doesn't look nice, but it'll do me untill I can sort it.