Dell Precision 3640 Tower upgrade guide: RAM, storage and CPU

Ciclo de vida y soporte

No se planean nuevas versiones de BIOS, firmware o controladores, por lo que una CPU más nueva podría no ser reconocida.

Las fechas no listadas no han sido publicadas por el fabricante o un tercero fiable.

RAM upgrade

There are four 288-pin desktop DDR4 DIMM slots (not laptop SO-DIMM) running in dual channel, and all of the memory is socketed - you can replace every stick. The board takes unbuffered UDIMMs only, in ECC or non-ECC variants. Registered or buffered server memory (RDIMM/LRDIMM) will not work.

Each slot takes up to 32 GB, for a maximum of 128 GB total (4 x 32 GB). Dell lists 8 GB as the smallest validated configuration. Speed is either 2666 or 2933 MT/s, and that is JEDEC stock speed only - the W480 chipset has no XMP or memory overclocking, so faster modules just run at stock or downclock.

How fast your RAM runs depends on the CPU. 2933 MT/s needs a Core i7/i9 or a Xeon; Core i3/i5 run 2666 MT/s. One caveat here: Dell's documents are not consistent about Xeon memory speed - Dell's memory note says Xeon supports 2933, while Dell's processor table lists all Xeon W-1200 chips at 2666. Intel's own specs put the 80 W Xeon W-1250/1270/1290 at 2666 and the 125 W P variants at 2933. In practice your RAM runs at whatever the installed CPU supports, so don't pay a premium for speed you can't use.

ECC memory is a CPU feature here. It works with a Xeon W-1200 (and the Core i3-10100 also supports ECC); Core i5/i7/i9 are non-ECC only. If you go ECC, it must be unbuffered ECC UDIMM.

Finally, fit two or four sticks rather than one. Dell recommends 2 or 4 DIMMs because single-channel memory hurts performance, especially if you are using the integrated graphics.

Consejos de compra

• Buy unbuffered DDR4 UDIMM (288-pin desktop) - never RDIMM or LRDIMM
• Don't pay extra for 3200 MT/s or faster; it won't run above 2933 and there is no XMP
• To hit 128 GB you need 4 x 32 GB UDIMMs, the priciest DDR4 modules around
• Match your CPU: ECC only with a Xeon W-1200 (or Core i3-10100)

Storage upgrade

M.2 slots. The motherboard has two M.2 2280 Key-M slots for NVMe SSDs on PCIe 3.0 x4. One of the two also accepts a SATA M.2 SSD; the other is NVMe only. They are 2280 only - shorter 2242/2260 or longer 22110 drives need an adapter. Because the slots are PCIe Gen 3, a Gen 4 or Gen 5 drive will work but is capped at roughly 3.5 GB/s, so there is little point paying for the newest generation.

There is a separate M.2 2230 Key-E slot on the board, but it is reserved for the Wi-Fi/Bluetooth card and cannot be used for storage. If you want a third M.2 SSD, it requires the proprietary Dell Ultra-Speed Drive interposer card, a Dell-specific PCIe adapter that is hard to find. Be aware that it occupies one of the expansion slots - in the x16 slot it displaces your graphics card.

Drive bays. In addition to the M.2 slots there are up to 4 x 2.5-inch SATA bays or up to 3 x 3.5-inch SATA bays (mixed configurations are supported), all SATA 6 Gbps. The 2.5-inch carriers are designed for 7 mm z-height drives - thicker 9.5 or 15 mm drives will not fit. Dell brackets and cables for the extra bays were not included on every build, so check your chassis and the service manual for the part numbers you are missing before buying bare drives.

Dell's validated factory sizes are 2 TB for the M.2 drives, 2 TB for 2.5-inch drives and 8 TB for enterprise-class 3.5-inch drives. Those are the sizes Dell tested and shipped, not hard limits - larger aftermarket drives generally work, but Dell does not validate them. As a rough guide, Dell's option list tops out at 2 TB for 5400 rpm 2.5-inch drives and 4 TB for consumer 3.5-inch drives.

One slot note while you are inside: the third full-height expansion slot is genuine legacy PCI, not PCIe, so modern cards will not fit it.

Consejos de compra

• M.2: buy 2280 NVMe drives; only one slot also takes SATA M.2
• Gen 3 slots cap every drive around 3.5 GB/s - Gen 4/5 premium is wasted
• 2.5-inch drives must be 7 mm thick to fit the carriers
• Check you have Dell brackets and SATA cables before ordering extra bare drives
• Bigger than 2 TB (M.2/2.5") or 8 TB (3.5") usually works but is untested by Dell

CPU upgrade

The processor is socketed (LGA 1200) on Intel's W480 chipset, so it is replaceable - but the upgrade path ends with 10th Gen Comet Lake. Dell lists Core i3-10100, i5-10500/10600/10600K, i7-10700/10700K, i9-10900/10900K and Xeon W-1250, W-1270 and W-1290 (each with a 125 W P variant). 11th Gen Rocket Lake or newer processors are not supported and won't work.

Maximum supported TDP is 125 W. That matters if your machine shipped with a 65 W CPU and you want a K-series or Xeon P part: you will need Dell's higher-performance heatsink, and you should check which power supply you have - Dell shipped 300, 460 and 750 W units. Note also that K-series CPUs cannot overclock on the W480 chipset, so a K part buys you clock speed and TDP headroom, not tuning freedom.

Two other CPU-related notes. A Xeon W-1200 enables ECC memory support (Core i5/i7/i9 do not), which is the main reason people swap to one. And the maximum memory speed depends on the chip you install, as described in the RAM section above.

A word on listings you may see: some reseller pages associate this board with Xeon E-2300 series chips. Dell's own documentation lists the Xeon W-1200 series, and no E-2300 part appears in Dell's supported CPU list - treat those listings with caution and check your exact service tag before buying.

Consejos de compra

• Stay within 10th Gen Comet Lake - 11th Gen is unsupported
• 125 W K/P chips need the higher-performance heatsink and an adequate PSU
• Choose a Xeon W-1200 if you want ECC memory support
• Expect 2666 MT/s RAM with i3/i5 and non-P Xeon parts

Installation steps

1. Back up anything important before you open the case.

2. Shut down, switch the power supply off and unplug the mains cable. Press and hold the power button briefly to drain residual power.

3. Ground yourself - touch the metal chassis or use an anti-static strap - before handling components.

4. Open the case. The owner's manual and Dell's service manual show the exact disassembly for each part; follow them rather than forcing latches or covers.

5. Install the part: seat RAM sticks firmly until the latches click (use slots that give you two or four sticks), seat M.2 SSDs in the 2280 slots and secure them, mount SATA drives in 7 mm carriers, and for a CPU lift the socket lever, match the pin-1 marker, and apply fresh thermal paste with the right heatsink.

6. Close the case, reconnect the power, and switch on.

7. Enter the BIOS/firmware setup and confirm it sees the new RAM capacity, the drives and the CPU. Then install or update drivers as needed and check the system is stable.

Consejos de compra

• Point 5 is where Dell-specific parts matter: 7 mm drive carriers, missing SATA brackets/cables, the higher-performance heatsink for 125 W chips
• Check your power supply rating before a 125 W CPU
• Always confirm the new part is visible in the BIOS before reinstalling your operating system

Cómo ampliar

Antes de empezar

• Back up your data
• Power off, switch off the PSU and unplug the cable
• Ground yourself before touching components
• Consult the owner's manual and service manual for your exact chassis disassembly
• Check brackets, cables, heatsink and PSU before buying - not every build has them
• Confirm the new part is detected in the BIOS/firmware after installation

Pasos

1. How much RAM can the Dell Precision 3640 Tower take?
   128 GB maximum, using four 32 GB unbuffered DDR4 UDIMMs. All four slots are socketed and nothing is soldered.
2. Does it support ECC memory?
   Yes, but only with the right CPU - a Xeon W-1200 (the Core i3-10100 also supports ECC). Core i5/i7/i9 are non-ECC only. The ECC memory must be unbuffered UDIMM; registered server RAM will not work.
3. Can I install an 11th Gen CPU?
   No. The board is LGA 1200 on the W480 chipset and Dell supports 10th Gen Comet Lake processors only - Core i3/i5/i7/i9 and Xeon W-1250/1270/1290. Rocket Lake and later are not supported.
4. How many SSDs can I add?
   Two M.2 2280 NVMe SSDs fit on the motherboard (one slot also takes SATA M.2), plus the SATA drive bays - up to 4 x 2.5-inch or 3 x 3.5-inch drives. A third M.2 requires Dell's proprietary Ultra-Speed Drive interposer card, which takes an expansion slot.
5. Does it support PCIe 4.0 or Gen 5 SSDs?
   Physically a modern NVMe drive fits and works, but the M.2 slots are PCIe 3.0 x4, so speeds cap at roughly 3.5 GB/s. Gen 4/Gen 5 drives give you no benefit here.
6. What size hard drives fit?
   2.5-inch drives must be 7 mm z-height - thicker drives won't fit the carriers. Dell validated up to 2 TB for 2.5-inch drives and 8 TB for enterprise 3.5-inch drives; larger aftermarket drives generally work but are unvalidated. Dell brackets and cables for extra bays may be missing on your build.

Es bueno saberlo

• Dell's documents disagree on Xeon W-1200 memory speed (2666 vs 2933 MT/s); Intel's specs say the non-P parts are 2666 and the P parts 2933. Some listings mention Xeon E-2300 chips, which do not appear in Dell's supported CPU list.
• Capacity figures (2 TB M.2, 2 TB 2.5-inch, 8 TB 3.5-inch) are Dell's validated factory sizes, not hard limits - larger drives generally work but are untested by Dell.
• Dell's manuals can differ on minor details such as the number of SATA ports and included brackets; check your own build against the service manual for your service tag.

Preguntas frecuentes

How much RAM can the Dell Precision 3640 Tower take?

128 GB, using four 32 GB unbuffered DDR4 UDIMMs. Every slot is socketed - nothing is soldered.

Does the Dell Precision 3640 Tower support ECC memory?

Yes, but only with an ECC-capable CPU: a Xeon W-1200 (the Core i3-10100 also supports ECC). Core i5/i7/i9 do not. Use unbuffered ECC UDIMM - registered server memory won't work.

Can I put an 11th Gen (Rocket Lake) CPU in the Precision 3640 Tower?

No. Dell supports 10th Gen Comet Lake processors only - Core i3/i5/i7/i9 and Xeon W-1250/1270/1290. The upgrade path stops there.

How many SSDs does the Precision 3640 Tower support?

Two M.2 2280 NVMe drives on the motherboard (one of them also accepts a SATA M.2 SSD), plus up to 4 x 2.5-inch or 3 x 3.5-inch SATA bays. A third M.2 needs Dell's proprietary Ultra-Speed Drive interposer, which occupies an expansion slot.

Do PCIe 4.0 NVMe drives work in the Precision 3640 Tower?

They fit and run, but the M.2 slots are PCIe Gen 3 x4, so performance is capped at around 3.5 GB/s. A cheaper Gen 3 drive is the sensible buy.

Does the Precision 3640 Tower need a new heatsink for a faster CPU?

If you move from a 65 W CPU to a 125 W K-series or Xeon P part, yes - Dell specifies the higher-performance heatsink. Check which power supply is fitted as well (Dell shipped 300, 460 and 750 W options).

Documentos y referencias oficiales

• PDF Dell Precision 3640 Tower - Setup and Specifications (PDF)
  Official Dell reference for memory, storage and processor options
• Dell Precision 3640 Tower Service Manual
  Full disassembly, slot layouts and validated configurations
• Dell Precision 3640 Tower technical reference
  Convenient full specification listing
• Dell Precision 3640 Tower product page
  Manufacturer page, including the Ultra-Speed Drive option