AMD Opteron 246 socket: Socket 940

What the Opteron 246 is

The AMD Opteron 246 is a 2 GHz single-core server processor from December 2004. It runs one K8 core at 2 GHz with no turbo, so 1 core gives 1 thread. Cache is 1 MB of L2 on a 90 nm process. Power is rated at 85 W in a Socket 940 package with part number OSA246FAA5BL in the E4 stepping.

Troy moves the 200 series from 130 nm SledgeHammer to 90 nm with SSE3 instructions and a 1000 MHz HyperTransport link. The 246 at 2 GHz with 1 MB shares clocks with the SledgeHammer 246 at 89 W, yet the Troy bin trims power to 85 W while adding the newer instruction set. AMD listed the Troy 246 at 316 dollars in December 2004. The chip supports MMX, SSE, SSE2, SSE3, Enhanced 3DNow, NX bit and AMD64 with registered PC3200 DDR. A SledgeHammer 246 shares the number with different power and no SSE3, so codename decides expectations. This page covers the Troy E4 part.

Two-socket use defines the Troy 246. The leading 2 enables coherent pairing with a second 246 on a dual-processor board, giving two cores per chassis with shared memory coherence. That pairing suited departmental servers that needed per core speed with a modern instruction set.

Socket and motherboard compatibility

The Opteron 246 Troy fits Socket 940 dual-processor boards with registered DDR and Troy 200 series BIOS support. It needs a two-socket board qualified for 90 nm Troy parts, not just any SledgeHammer board. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Two-socket rack servers are the natural match. Boards listing Troy parts set voltage to 1.35 V to 1.40 V with SSE3 paths and 1000 MHz HyperTransport operation. SledgeHammer-only boards may seat the chip yet miss Troy microcode. A duplicate cpu_list row repeats the same Troy 246 spec, so one page covers both entries.

Memory, PCIe and cooling

Memory is registered DDR with ECC per socket, reaching PC3200. Each CPU needs DIMMs for balanced dual-socket bandwidth. Server modules only.

HyperTransport at 1000 MHz links the CPUs to each other and to the chipset, while expansion hangs off the chipset. No PCIe lanes originate on the die. Cooling uses matched 85 W heatsinks per socket with rack airflow. Both sockets need equal service for stable dual operation. DDR2 needs Socket F.

Upgrade paths

On Socket 940 the steps are the Opteron 248 at 2.2 GHz and the 250 at 2.4 GHz in Troy revisions for two-socket boards. The 246 HE at 55 W offers the same 2 GHz clocks for dense racks where listed. SledgeHammer 246 at 89 W is the 130 nm alternative without SSE3. Beyond Socket 940 a move to Socket F needs DDR2 boards. The 246 lifts with the lever, so swaps need no solder work.