IBM System x Tower Servers in India: x3100, x3400 and x3500 Compared
Quick answer: IBM (now Lenovo) System x tower servers are old but sturdy dual- or single-socket machines. The x3500 M4 (Xeon E5-2600 v2, DDR3) and x3500 M5 (Xeon E5-2600 v3, DDR4) are the large expandable towers, the x3400 M3 (Xeon 5600, DDR3) is the older mid-range tower, and the x3100 is a single-socket entry tower. All of them are withdrawn products, so the real questions for a buyer are which generation fits the job, what the exact unit contains, and who supports it after purchase. This guide lists the published specs for each model, then shows how to read a refurbished listing before you pay.
It is written for IT managers, small-business owners and sysadmins in India who found a refurbished IBM tower server and want to know what they are actually buying. Specifications below come from Lenovo Press product guides, which still host IBM’s System x documentation. Prices are not quoted because they depend on CPU, RAM and drives; Serverwale shows its IBM tower listings as “Request pricing”, so ask for a written quote for the exact configuration.
Which IBM System x tower server should you choose?
| Model | Sockets and CPU family | Memory | Drive bays (published maximum) | Best fit |
|---|---|---|---|---|
| System x3100 M5 | 1 × Xeon E3-1200 v3 (also Core i3, Pentium, Celeron options) | 4 DDR3 ECC UDIMM slots, up to 32 GB | 4 × 3.5" (simple- or hot-swap) or 8 × 2.5" hot-swap in the standard tower | Small office file, print and light application server |
| System x3400 M3 | Up to 2 × Xeon 5600 (4 or 6 cores) | 16 DDR3 slots, up to 128 GB with 8 GB RDIMMs | Up to 8 × 3.5" hot-swap or 16 × 2.5" hot-swap | Low-cost storage or legacy application server |
| System x3500 M4 | Up to 2 × Xeon E5-2600 v2 (up to 12 cores) or E5-2600 | 24 DDR3 slots, up to 768 GB with 32 GB LRDIMMs | Up to 32 × 2.5" hot-swap or 8 × 3.5" hot-swap | Virtualization, databases and storage-heavy builds in a tower |
| System x3500 M5 | Up to 2 × Xeon E5-2600 v3 (up to 18 cores) | 24 DDR4 slots, up to 768 GB RDIMM or 1.5 TB LRDIMM | Up to 32 × 2.5" or 12 × 3.5" hot-swap | Newer memory platform, optional GPU support |
Choose by workload, not by model number. A single-socket x3100 is enough for a shared drive and a few users. If you need many cores, large RAM or lots of disks, you are looking at the x3500 family. For other tower brands side by side, see our tower servers page and the rack vs tower comparison.
IBM System x3500 M4: the expandable tower
The x3500 M4 is the model Serverwale lists as a refurbished IBM System x3500 M4 5U tower server. Lenovo Press documents it as a tower that converts to a 5U rack server, with up to two Intel Xeon E5-2600 v2 processors (up to 12 cores) or earlier E5-2600 processors (up to 8 cores).
- Memory: 24 DDR3 sockets (12 per processor), with RDIMM, UDIMM or LRDIMM, but never mixed. With E5-2600 v2 the maximum is 768 GB using 24 × 32 GB LRDIMMs, or 384 GB with 24 × 16 GB RDIMMs. Speed is up to 1866 MHz with v2 processors and 1600 MHz with the original E5-2600.
- Storage: up to 32 × 2.5" hot-swap SAS or SATA bays, or up to 8 × 3.5" hot-swap. Controllers listed include ServeRAID M1115 and M5110 (6 Gb) and M5210 (12 Gb); RAID 0, 1 and 10 are standard, while RAID 5, 6 and their variants need optional upgrades.
- Expansion: up to eight PCIe slots with two processors (six with one). All are PCIe 3.0 except slot 1, which is PCIe 2.0.
- Power: up to two redundant hot-swap supplies of 550 W, 750 W or 900 W, rated 80 PLUS Platinum.
- Management and network: IMM2 management; remote presence and blue-screen capture need the optional IMM Advanced Upgrade. Four integrated 1GbE ports.
- Size: the tower is 218 mm wide, 750 mm deep and 440 mm high, weighing 25 kg to 39.8 kg depending on configuration. Plan floor space and lifting, not just a desk corner.
Lenovo Press marks the x3500 M4 as withdrawn from marketing and names the x3500 M5 as its replacement. Standard models were announced in March 2012 (E5-2600) and September 2013 (E5-2600 v2).
IBM System x3500 M5: the DDR4 generation
The x3500 M5 (machine type 5464) keeps the tower or 5U layout but moves to Xeon E5-2600 v3 processors with up to 18 cores per CPU and DDR4 memory at up to 2133 MHz. Lenovo Press lists 24 DIMM sockets, up to 768 GB with RDIMMs or 1.5 TB with 64 GB LRDIMMs. The guide lists v3 processors only, so if a refurbished listing names a different CPU generation, ask the seller to show the CPU model number on the unit.
- Storage: up to 32 × 2.5" hot-swap or 12 × 3.5" hot-swap, with ServeRAID M1215 or M5210 controllers, or an N2215 HBA for non-RAID use.
- Expansion: up to seven PCIe 3.0 slots with two processors (four with one). Slots 3 and 6 support double-wide GPUs, and the guide lists support for up to two NVIDIA Quadro or Tesla cards from a defined list; the two cards must be identical.
- Power: up to two hot-swap supplies, 550 W to 1,500 W Platinum, or 750 W Titanium.
- Management and network: IMM2.1, and four Gigabit Ethernet ports.
The change from M4 to M5 matters for upgrades: DDR3 and DDR4 memory are not interchangeable, so RAM bought for one generation will not fit the other.
IBM System x3400 M3 and x3100: older and smaller
x3400 M3. Announced in February 2011, this 5U tower (convertible to rack) takes up to two six-core or quad-core Xeon 5600 processors and has 16 DDR3 sockets, with a 128 GB maximum using 8 GB RDIMMs. Drive options range from four 3.5" simple-swap SATA drives to eight 3.5" or sixteen 2.5" hot-swap drives, but Lenovo Press notes that the single 670 W fixed power supply limits a configuration to four 3.5" or eight 2.5" drives; the redundant option is two 920 W supplies. Its expansion slots are PCIe 2.0, a clear step behind the x3500 line. It suits low-demand storage or a legacy application, not new virtualization.
x3100 M5. A single-processor tower with Xeon E3-1200 v3 options, four DDR3 ECC UDIMM slots and a 32 GB maximum. The compact tower takes four 3.5" simple-swap bays; the standard tower takes four hot-swap 3.5" or eight 2.5" hot-swap bays and up to two 430 W hot-swap supplies. Serverwale’s IBM page also lists the x3100 M4 as an entry model, so confirm the exact generation printed on the unit. The x3100 is only sensible for small, light workloads.
How to read a refurbished IBM tower server listing
- Identify the generation from the CPU and RAM type. Xeon 5600 with DDR3 is the x3400 M3 era; Xeon E5-2600 v2 with DDR3 is x3500 M4; Xeon E5-2600 v3 with DDR4 is x3500 M5.
- Count what is actually installed. Maximums are not contents. Ask for the number of CPUs, DIMMs and their capacity, drive bays populated, RAID controller model and whether the RAID cache is present. See our refurbished server buying checklist.
- Check the power supplies. Redundancy needs two supplies, and the wattage limits how many drives and GPUs the unit can run.
- Confirm management. IMM2 gives remote management, but remote presence needs an optional upgrade key. Ask whether it is included.
- Ask what is tested and get the warranty in writing. Serverwale describes its units as tested before dispatch and states a 1-year warranty, with extended warranty for 2 additional years available at extra cost. Confirm what the warranty covers and get it in writing on the quote and invoice. A post-delivery testing checklist helps you verify on arrival.
- Plan for parts. These are withdrawn products; ask how spare drives, PSUs and fans are sourced. Our guide to spare parts for older Dell, HP and IBM servers covers what to expect, and the drive price list helps you budget.
Processor choice also changes cost; see the Intel Xeon generations buying guide and the E5-2600 v2 price list for the x3500 M4 platform.
Is an old IBM tower server still worth buying?
It can be, for the right job. A tower with ECC memory, hardware RAID and redundant power gives a small office real server reliability without a rack, and refurbished prices are far below new. The trade-offs are honest ones: older CPUs use more power per unit of work than current ones, firmware updates are no longer being developed, and some modern operating-system and hypervisor versions may not support older hardware, so check your software’s hardware compatibility list before you buy. If you need long vendor support or newer CPUs, compare a current-generation tower or a rack server. Our IBM rack servers page and IBM rack server price guide cover the rack side of the System x range.
Lenovo took over IBM’s x86 server business in 2014, which is why the same machines appear under IBM and Lenovo names. Documentation is on Lenovo Press, but support for a given refurbished unit comes from the dealer you buy from, so choose one that offers an annual maintenance contract.
Frequently asked questions
What is the difference between the IBM System x3500 M4 and M5?
The x3500 M4 uses Xeon E5-2600 v2 processors (up to 12 cores) and DDR3 memory, up to 768 GB. The x3500 M5 uses Xeon E5-2600 v3 processors (up to 18 cores) and DDR4 memory, up to 1.5 TB with LRDIMMs. The M5 also lists optional support for up to two NVIDIA GPUs. DDR3 and DDR4 are not interchangeable.
How much RAM can an IBM x3500 M4 take?
It has 24 DDR3 sockets. With E5-2600 v2 processors, Lenovo Press lists up to 768 GB using 32 GB LRDIMMs, 384 GB using 16 GB RDIMMs, or 128 GB using 8 GB UDIMMs. Memory types cannot be mixed, and what a unit actually contains depends on how it was configured.
Can an IBM tower server be mounted in a rack?
The x3400 M3, x3500 M4 and x3500 M5 are documented as tower or 5U rack servers, using a rack conversion kit. Ask whether the kit and rails are included, because they are separate items.
Is the IBM System x3500 M4 still supported?
Lenovo Press lists it as withdrawn from marketing, so it is no longer sold new. Parts and service for a refurbished unit come through the dealer, so ask about spares and an AMC before buying.
Which IBM tower server is best for a small office?
For a few users, file sharing and light applications, a single-socket x3100 is enough. For virtualization, a database, or many disks, the x3500 M4 or M5 gives far more memory and drive bays. Size to your workload and check that your software supports the hardware.
Where can I buy a refurbished IBM tower server in India?
Serverwale lists refurbished IBM System x3500 M4 and other IBM tower and rack servers to buy or rent. Pricing is on request, so share the CPU, RAM and drive configuration you need and ask for a written quote with the warranty period.
Get an IBM tower server quote
Tell us your workload, memory and drive needs, and we will check stock and quote the exact configuration. Call or WhatsApp +91-87962-44410, or contact us. You can also browse refurbished servers in India, compare the price index or look at the x3500 M4 listing.
Sources: Lenovo Press product guides, System x3500 M4 (TIPS0852), System x3500 M5 (TIPS1242), System x3400 M3 (TIPS0808), System x3100 M5 (TIPS1165); IBM Form 8-K, 2014 (sale of the x86 server business to Lenovo); Serverwale IBM page and tower servers page. All guides are for withdrawn products; confirm the specification of the exact unit before buying. Position as of 10 October 2026.