AMD Athlon X4 845 socket: Socket FM2+

What the Athlon X4 845 is

The Athlon X4 845 brings Carrizo to FM2+ for towers that already carry a graphics card. It launched on February 2, 2016 with a 3.5 GHz base and up to 3.8 GHz boost at 65 W. AMD targets first time builders who need four real cores at a low price.

Two megabytes of L2 with 1 MB per module feed office work and light creation without L3. The steady base clock keeps everyday apps responsive. Four threads cover foreground tasks plus background updates.

There is no integrated GPU, so a discrete card is required for display output. The process is 28 nm on a 250 mm2 die with 3100 million transistors. The multiplier is unlocked for tuning where boards allow it. DDR3-2133 in two channels supports up to 64 GB on capable boards.

Shops value the part for repair jobs where an FM2+ board must stay in service. The 65 W rating fits existing towers and power supplies. A 74 C case limit leaves headroom for summer rooms with basic airflow.

Socket and motherboard compatibility

The Athlon X4 845 fits Socket FM2+ on FM2+ boards only. A88X, A85X, A78, A75 and A68H boards list the chip with DDR3 slots and PCIe slots for discrete graphics. Makers add late Carrizo IDs with 2016 BIOS builds.

Early FM2+ stock may need an update before posting. FM2 boards lack the extra pins for full support. AM4 boards cannot take this PGA chip despite similar names. The Socket vs chipset: what decides whether a CPU works guide details generation rules.

Single socket desktops are the deployment. Growth means another FM2+ quad core on the same board rather than a new platform. Display choice stays with the discrete card, so outputs follow the card bracket rather than the board rear.

Memory, PCIe and cooling

DDR3-2133 in two channels up to 64 GB covers budget builds with a discrete card. Dual channel operation lifts minimum frame rates in particular. Start with 8 GB for office use.

PCIe 3.0 with 8 lanes from the CPU allows a discrete GPU plus board devices per FM2+ layout. Most builds pair a low profile card for office displays or a modest gaming card for 1080p. Chipset lanes add storage and USB.

Cooling follows the 48 by 96 mm FM2+ pattern in the CPU cooler compatibility by socket guide. A 65 W stock cooler suffices for office loads. Towers help hold boost during longer exports. Keep filters clean where rooms run dusty.

Upgrade paths

On the same socket, the AMD A8-7680 adds Radeon R7 graphics at 45 W for builds that must run without a discrete card. Athlon X4 parts without graphics suit headless nodes where listed. Both share FM2+ boards and DDR3.

AM4 APUs with DDR4 move newer fleets to current memory. They require new boards and DIMMs. The A8-7680 covers quad core office towers where graphics must stay integrated.

Past FM2+ budget AMD desktops use AM4. The Athlon X4 845 covers quad core towers where a discrete card is already present and the board must stay.