A better alternative if you want to take the cost out
Hewlett-Packard has devised a siamese-twin CPU server blade for those monstrous data centers with nowhere to spread out. HP pitches its new ProLiant BL2x220c G5 as the first blade with two independent servers combined into a single blade enclosure. The twofer is intended for large "scale-out" operations that require massive …
This is more like idataplex competitor aimed at ultra high compute density market. Each blade can have only 8GB max RAM to feed 8 cores, and little IO, but you get so many of these discrete 2-socket physical servers in little space. Most HPC/web2.0 customers probably do not need a lot of memory so this may work out well for them. HP is charging quite a premium for this kind of density with this solution. While idataplex has liquid cooling integrated, it would be interesting to know whether there is any integrated liquid cooling at work here.
Fuzz is right, It's 16GB per server and they're not being aimed at heavy VM usage, more for compute-heavy or forced-scale-out environments.
Also in reference to the IBM iDataplex, they're not in the same league - two racks-worth of these this HP blade model equals 2048 xeon cores and 4TB of memory and are already shipping. It's hard to find details on the IBM system but it looks like they only get either 800 or 1600 cores into the same space, plus of course you end up building your environment two-racks at a time - not always 'do-able'. Oh and they're coming in July.