IBM System x3650 M2

  • Editors' rating
    7.8 Very good


  • Light path diagnostics
  • Predictive failure analysis
  • Wide range of add-on options, support and other services


  • Maximum RAM capacity of 128GB
  • 2.5in. disks only
  • 2 Gigabit Ethernet ports
  • Fans are difficult to swap

IBM’s latest rack-mount Xeon 5500 servers are a little different to others we've looked at, and not just technically. That's because they're not only sold by IBM and its resellers, but also through Lenovo, which licences the IBM design, manufactures independently and sells the same products under the ThinkServer label. The end result is almost identical, apart from minor differences in firmware. There are also differences in terms of management add-ons, as the Lenovo ThinkServer is aimed at smaller businesses rather than the large enterprises on which IBM tends to focus.

Both vendors offer 1U and 2U implementations, each dual-socket and able to take dual- or quad-core Xeon 5500 processors. We looked at the 2U IBM System x3650 M2, also known as the ThinkServer RD220 when purchased from Lenovo.

Spot the difference: IBM's System x3650 M2 (top) is licensed and manufactured by Lenovo as the ThinkServer RD220 (bottom).

Company logos and model names apart, the two models are hard to differentiate, although they're quite different from the other 2U rack servers we've reviewed in a number of ways. The chassis is conventional enough, with the usual IBM build quality providing easy tool-free access to all of the major components. Cooling is handled by a set of variable-speed fans with the interior divided into three separately monitored zones. These are marked in red, and the rather large fans are designed to be hot-plugged — although we found them a little bit fiddly to remove and replace.

The front panel features a pop-out light path diagnostics panel that enables a malfunctioning systm component, such as a fan or a DIMM, to be quickly identified. There's also a pair of USB ports and a video interface, with the hot-plug disks all arranged alongside. Power is delivered by a redundant pair of 675W supplies that slide into slots at the rear, alongside two Gigabit Ethernet ports — the same as the Fujitsu Primergy RX300 S5, but only half the number found on the other 2U rack servers we've reviewed (although TCP offload is supported).

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Similarly, you're a bit restricted when it comes to further expansion, with just four PCI Express slots compared to six on the HP and Sun servers and seven on the Fujitsu. An optional pair of PCI-X slots can also be configured.

In terms of layout, the IBM motherboard is distinguished by staggered processor sockets and only 16 DIMM slots arranged in two banks of eight, between them. The placing of the Xeon 5500 chips isn't of any relevance, but with just 16 memory slots the IBM/Lenovo server can only accommodate 128GB of RAM, compared to 144GB on rival 18-slot servers. That may not be a big issue for a lot of customers, but those wanting to get the most out of their investment by hosting lots of virtual machines or large memory-resident databases may feel the restriction.

On the plus side, up to 3.6TB of internal storage can be accommodated inside the IBM chassis, although you're limited to 2.5in. drives only as there's no ironwork to take 3.5in. disks. Still, twelve hot-plug bays can be specified altogether which is good — reducing to eight if you want to fit an internal backup drive. Plus, if you don't need hot-swap there's a cheaper 'simple-swap' option where the server has to be switched off to change disks. You get a choice of SATA, SAS and SSD drives, managed by an upgradeable LSI MegaRAID controller.

Like the competition, IBM makes it possible to specify an embedded hypervisor — in the case of the IBM server, using an internal bootable USB port. Currently only a VMWare hypervisor is available to order but others, including Hyper-V, are planned and there's nothing to prevent customers booting an independently sourced hypervisor using this interface if they wish.

Remote server management is handled by the Integrated Management Module (IMM) on the IBM motherboard, which has its one dedicated fast Ethernet port. This offers a lot of the functionality provided by the RSA II adapter employed in previous servers, although to get support for virtual media and remote KVM you need the optional Virtual Media Key to plug into the internal or one of the external USB ports.

IMM is in both IBM and Lenovo servers, but when it comes to managing servers the two vendors start to diverge. Lenovo bundles its EasyManage software, which is aimed at small businesses with limited technical resources, while IBM ships customers its Systems Director suite. The latter is a lot more extensive, with power monitoring/capping tools and facilities to dynamically throttle processors.

Another benefit of buying from IBM is its predictive failure technology, whereby components can be swapped out before they actually go wrong. The IBM support structure is also much larger, although on-site servicing is handled by IBM Global services regardless of vendor and Lenovo does have its own support staff to deal with software and operational issues.