Dell said HP was making an unfair comparison in an announcement of its latest ProLiant blade servers, when it said one could replace three two-socket Dell M610 blades with one BL660c four-socket blade by HP.

In an email to DatacenterDynamics, a Dell spokeswoman said the claims by HP were no big surprise, since it was not an “apples-to-apples” comparison. “The Dell M610 is a previous-generation two-socket Dell server; HP’s is a current-generation four-socket,” Sally Stevens, VP of PowerEdge server marketing at Dell, wrote.

A fair comparison would be to put HP’s BL660c against Dell’s latest-generation M820 blade, as both have four sockets. “Dell offers 50% more memory (and thus VM capacity) with the same processor architecture,” Stevens said.

Indeed, the Dell blade’s maximum memory capacity, with its 48 DIMM slots, is 1.5TB, according to specs published on the company’s website. HP’s BL660c has 32 DIMM slots, which give it a maximum memory of 1TB, according to its website.

Both products are based on Intel’s Xeon E5-4600 processors.

As an alternative to upgrading older Dell M610 with the product HP compared them to, Stevens suggested Dell’s two-socket, half-height M620 blades.

HP was pitching its four-socket servers as replacement for two-socket ones, because the former can support a lot more VMs than the latter. A four-socket system has a much larger pool of memory and compute than a two-socket one, which gives companies a way to virtualize beyond the common 50-80% virtualization rate, according to HP.