Yes. Use Configure & Buy to open the current CTO listing and choose its available options. Contact us for requirements outside that listing.

No. It describes platform options for its document edition. Check your installed processor, memory, chassis, controller, power supply and expansion components before selecting parts.

For rack-constrained workloads, often yes. The R640 is a 1U dual-socket platform, and the specifications on this page — up to two Intel Xeon Scalable processors (1st or 2nd Generation) and 24 DIMM slots — are platform capabilities rather than a description of any particular system. What a given server contains depends on how it is configured. The R640 suits virtualisation, application and web hosting, and dense deployments where rack units are the scarce resource. Our refurbished configure-to-order R640 is the option customers choose most often, because you pay only for the processors, memory and storage the workload needs.

The decision is mostly about the chassis rather than processor support. Both platforms support Intel Xeon Scalable processors and both provide 24 DDR4 DIMM slots, so neither is inherently the faster machine — actual performance depends on the processors, memory and cooling fitted to the specific system you configure. The difference that matters is physical. The R640 is a 1U chassis, documented for up to ten 2.5-inch front drive bays plus up to two rear bays. The R740 is a 2U chassis, documented for up to sixteen 2.5-inch or eight 3.5-inch drives and up to eight PCIe Gen 3 slots. Choose the R640 when rack space is the constraint; choose the R740 when you need more drives or more expansion cards. All of those are platform options drawn from the manufacturer documents — confirm them against the chassis and backplane in the configuration you are quoted.

Four things decide whether a configuration will work. First, the processor: the installed CPU count affects how much memory and expansion you can use, so confirm the exact CPU and firmware requirements for your system. Second, memory: confirm DIMM type, the slots already populated and the population rules for your CPU count. Third, storage: drive size, backplane, controller and carriers have to match one another — a 1U chassis is less forgiving here than a 2U one. Fourth, the physical build: power supplies, rails and bezel. Our configurator resolves all four for you, and anything outside it can be priced through a custom quote request.

It can be changed. Dell documents the Network Daughter Card as a serviceable component, with a removal and installation procedure published in the PowerEdge R640 Installation and Service Manual. So this is not a permanent decision.

It is, however, a planned-maintenance job rather than a live upgrade. Replacing the card means powering the server down, opening the chassis and sourcing a compatible card, and the server is offline while that happens. Choosing at the point of purchase avoids that: the card is installed and the system is functionally tested with it in place before shipment.

One reason to decide carefully now is that the R640 option list is wider than what most comparison articles describe. Alongside the usual 1GbE Base-T and 10GbE Base-T and SFP+ cards, the configurator also offers Intel X710 with 2x or 4x 10GbE SFP+ and a Mellanox ConnectX-4 with 2x 25GbE SFP+. If your switching already supports 25GbE, taking that card at build time avoids a later chassis-open swap; if it does not, a 10GbE card is the sensible choice and 25GbE is what you would be upgrading to.

For help choosing between the connection types themselves, see the network daughter card selection guidance on the R740 page — the same reasoning applies here. These are the options this platform offers, not the card included in any particular quoted configuration. Configure a PowerEdge R640; networking is covered by our standard 3-year warranty.