When you buy VPS you get dedicated server grade ECC RAM, Raid 10 HDD space, ability to revert to snapshot, make backup of whole system image, latest Quad Core Xeon Nehalem 56xx processor speed, RAID controller with its own memory, and lot more. However, be aware that this is not the case with all VPS providers. VpsWebServer is completely different, and you can even run benchmarks and see that dedicated servers with similar speed are 3-6 times more expensive, and you also lose all the flexibility VPS hosting offers.
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