Dell today refreshed its storage  portfolio with the introduction of two new iSCSI storage arrays.  The PS4100 and PS6100 control arrays will be replacing the existing  PS4000 and PS6000 models, bringing with them support for 2.5-inch disk drives. The PST4100 is offered in two configurations, one of them being a U2 rack with 24 2.5-inch drives and a total of  21.6TB. The PS6100, in turn, can also be setup like that with . 15K and 10K disk drives , in addition to  400GB  worth of SSDs.

“Dell claims “PS6100 customers can achieve the same performance for their typical workload using half the number of arrays, and receive 50 per cent more expansion capacity when compared with the previous generation,” according to a report from The Register.

The second storage update from Dell today is the latest version of firmware it’s rolling out. Version 5.1 features Data Centre Bridging for 10GbitE iSCSI. The update also packs data tiering across group nodes or chassis, meaning data is automatically moved to a different node when latency surpasses a certain level. This provides a 3X performance boost, according to product line executive director Travis Vigil.

Beyond storage, Dell’s making a few top end changes this week as well.  The company announced it has added to more speakers to the upcoming Dell World 2011 conference.  Vivek Kundra, former White House CIO and Michelle Bailey, VP of research at  IDC’s Enterprise Platforms and Datacenter Trends unit, will be speaking at the gathering. The two are joining a list of speakers that include the CEOs of Intel, VMware, Salesforce.com, Microsoft and Dell itself.

Competitor Hewlett-Packard also had a big storage update today.  The company launched the new  HP Peer Motion and HP P10000 3PAR Storage System. This latest extension of HP Converged Storage focuses on slashing costs and scaling based on usage.