Re: About High End DELL servers!
High End Dell servers would encompass any of their R710 or R720 models - they're designed to fit into a 2U rack space and offer a high level of performance relative to the number of CPUs and cores they pack.
For example, at work right now we use R710's, the main one we use is a 2 processor Xeon (quad core, with hyperthreading, so each chip can pitch in 8 threads) with 64 GB of RAM running VMWare. A purchase we're making next year will upgrade to the R720's which will have two octo-core (8 core) CPUs with hyperthreading and 128GB of RAM.
They have higher end models, but these would be the basis of what I consider Dell's "high end" servers. They also have a 1U model that can pack in 2P/8C - I believe it's the R620.
Dell's Enterprise level support / sales folks are great. If you need specifics, just go to the source - ask them. Be honest about what you're doing, and they'll generally do what they can to help out.