Intel Core i5-3550S socket: LGA 1155

What the Core i5-3550S is

Intel Core i5-3550S is a low power quad core Ivy Bridge desktop processor that Intel released in April 2012. It runs at 3.0 GHz base with Turbo Boost 2.0 to 3.7 GHz, with 6 MB Intel Smart Cache and 4 threads. Power is rated at 65 W, which is notable because base clock matches the older 77 W pace while turbo reaches higher. The 22 nm process makes that mix possible.

Graphics are Intel HD Graphics 2500 at 650 MHz to 1150 MHz, the higher ceiling marking the faster Ivy bins. The block handles office displays and video, with Quick Sync for encodes. The chip includes the dual channel DDR3 controller, AVX and virtualization support of the Ivy family.

The model suited buyers who wanted near 77 W speed without 77 W heat. Single thread bursts touch 3.7 GHz, while all core loads hold near 3.0 GHz inside 65 W. Towers pair it with H77 or B75, 8 GB to 16 GB of RAM and an SSD. The How to find your CPU socket type guide helps confirm the board in a used system.

Socket and motherboard compatibility

The Core i5-3550S fits LGA 1155 in FCLGA1155 form. 7 series boards that launched with Ivy Bridge boot it directly, including H77, Z77, B75 and Q77. Most 6 series H61, H67, P67 and Z68 boards accept it after a BIOS update with Ivy Bridge microcode, except B65, Q65 and Q67. Fit the update first where needed.

At 65 W the chip drops into slim and standard boards without power concerns, which is why office makers favored S parts. Board selection turns on display outputs, slots and management features. The Socket vs chipset: what decides whether a CPU works guide explains the chipset split, and Intel Core i5-3550 shows the 77 W twin for comparison.

Memory, PCIe and cooling

Memory support is DDR3-1333 and 1600, two channels, up to 32 GB for 25.6 GB/s. Two matched DIMMs reach that rate and feed the shared graphics block. ECC is not supported, and DDR4 requires a newer socket.

PCI Express is 16 lanes from the CPU at PCIe 3.0, set as 1x16, 2x8 or 1x8 plus 2x4. Office systems often stay on HD 2500 alone, since it drives two displays. A 2012 mainstream card matches the quad cores where light 3D or extra monitors are planned.

Cooling follows the 65 W S pattern with a 69.1 C case limit. The stock cooler handles bursts quietly, while a small tower steadies long turbo holds. Mounting is 75 × 75 mm push pin, common across LGA generations.

Upgrade paths

On LGA 1155 the Core i5-3550S can step to higher Ivy quads on the same board, including 77 W parts where the cooler allows. Memory, storage and often the cooler carry over, so only the chip and paste change. A reference slower quad on the same socket is Intel Core i3-3220 in dual core form for scale, though it drops two cores.

A platform move to DDR4 boards such as LGA 1200 needs a new board, new RAM and a new mount. Keep the 3550S board for efficient office use where its 3.7 GHz bursts still feel quick.