IBM System x3650 M4 review

A 2U rack server, which comes with Intel Xeon processors and introduces IBM's pay-as-you-grow design.

Memory choices

The server's 24 DIMM slots are all enabled in dual CPU configurations. The maximum 768GB is supported by 1333MHz LR (load reduced) DIMMs, standard RDIMMs are limited to 384GB and cheaper UDIMMs are good for 64GB.

The x3650 M4 is one of the first of IBM's servers to be offered with HyperCloud DIMMs (HCDIMMs). These are expensive but support up to 384GB running at 1333MHz with three DIMMs per channel and claim a 25 per cent performance boost over standard RDIMMs.

IBM System x3650 M4 - 4

IBM System x3650 M4 - 4

Along with six PCI-e slots, the x3650 M4 has quad Gigabit ports plus a mezzanine connector for dual 10GbE cards

Network connections are more flexible than HP as the server has four embedded Gigabit ports plus a dedicated connector for an Emulex dual-port 10GbE mezzanine card. The DL380p Gen8 has one connector which supports either quad Gigabit or dual 10GbE mezzanine cards.

The price includes a pair of 750W hot-plug supplies which will cover most workloads but you can opt for 550W or 900W modules. With Windows Server 2008 R2 Enterprise idling along, we recorded a draw of 98W and with SiSoft Sandra putting the processors under maximum load this peaked at only 222W.

Internal cooling is handled by a bank of four hot-plug fans in front of the processors. With a DL380p Gen8 sitting next to the x3650 M4 on the lab bench, we found noise levels to be very low with nothing between the two.


If you want the best remote server management features on the planet then check out HP's DL380p Gen8 and its new iLO4 chip. However, these do come at a premium price making IBM's x3650 M4 a good choice for SMBs that want a more affordable 2U rack server that has the capacity to grow with them.


SMBs and enterprises looking for a general purpose 2U rack server or a solid platform to run their critical apps on will find IBM’s new x3650 M4 a worthy candidate. Management features aren’t as sophisticated as those found in HP’s new ProLiants but it is good value and is scalable.

Chassis: 2U rack

CPU: 2 x 2.3GHz Xeon E5-2630

Memory: 16GB 1.35V DDR3 RDIMM memory expandable to 256GB (768GB with LRDIMMs)

Storage: 2 x 300GB IBM 10k SAS 2 hot-swap hard disks (max. 16)

RAID: IBM ServeRAID-M5110e with 512MB cache and BBU

Array support: RAID0, 1, 10

Expansion: 6 x PCI-e Gen3

Network: 4 x embedded Gigabit

Power: 2 x 750W hot-plug supplies

Management: IMM2 Advanced

Software: IBM Systems Director 6.3

Warranty: 3yrs on-site NBD

Dave Mitchell

Dave is an IT consultant and freelance journalist specialising in hands-on reviews of computer networking products covering all market sectors from small businesses to enterprises. Founder of Binary Testing Ltd – the UK’s premier independent network testing laboratory - Dave has over 45 years of experience in the IT industry.

Dave has produced many thousands of in-depth business networking product reviews from his lab which have been reproduced globally. Writing for ITPro and its sister title, PC Pro, he covers all areas of business IT infrastructure, including servers, storage, network security, data protection, cloud, infrastructure and services.