AMD Opteron 240 EE socket: Socket 940

What the Opteron 240 EE is

The AMD Opteron 240 EE is a 1.4 GHz energy-efficient single-core server processor from February 2004. It runs one K8 core at 1.4 GHz with no turbo, so 1 core gives 1 thread. Cache is 1 MB of L2 on a 130 nm process. Power is rated at 30 W in a Socket 940 package with part number OSB240CSP5AU in the CG stepping.

EE bins the same 1.4 GHz and 1 MB rating as the standard 240 at 82 W down to 1.15 V for 30 W operation. AMD sold the EE bin at 851 dollars for dense two-socket racks, against 198 dollars for the standard 240 in May 2004. The premium bought lower heat per node, smaller heatsinks and more nodes per kilowatt. The chip supports MMX, SSE, SSE2, Enhanced 3DNow, NX bit and AMD64 with registered PC3200 DDR and an 800 MHz HyperTransport link.

Two-socket density is the use case. A pair of 240 EE parts at 30 W each gives two cores per chassis at 60 W of CPU power, against 164 W for standard parts. That gap lets dense blades pack more chassis per rack without new power feeds.

Socket and motherboard compatibility

The 240 EE fits Socket 940 dual-processor dense servers with registered DDR memory and EE SledgeHammer BIOS support. It needs a two-socket board qualified for 30 W EE operation at 1.15 V. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Dense two-socket blades are the natural match. Boards listing EE parts set voltage and fan curves for low power operation. Standard power boards may seat the chip yet miss EE power tables. Single-processor 140 EE parts suit one-socket boards instead.

Memory, PCIe and cooling

Memory is registered DDR with ECC through the on-chip controller, reaching PC3200. Each socket needs its own DIMMs for balanced bandwidth. Only registered modules boot.

HyperTransport at 800 MHz ties the two CPUs to each other and to the chipset, while expansion hangs off the chipset. No PCIe lanes originate on the die. Cooling uses vendor qualified 30 W server heatsinks per socket with shared rack airflow. Low power still needs clean vents, since dense nodes starve quickly when filters clog. DDR2 needs Socket F.

Upgrade paths

On Socket 940 EE operation stays inside low power bins, with standard power 242 and 244 parts as higher clock alternatives where cooling allows. Troy successors on 90 nm offer SSE3 paths where listed. Beyond Socket 940 a move to Socket F needs DDR2 boards. The 240 EE lifts with the lever, so swaps need no solder work.