AMD Athlon 650 socket: Socket 462

What the Athlon 650 is

The AMD Athlon 650 is a 650 MHz single-core desktop processor from June 2000. It runs one K7 Thunderbird core at 650 MHz with no turbo, so 1 core gives 1 thread. Cache is 256 KB of full-speed on-die L2 with 128 KB of L1 on a 180 nm process. Power is rated at 38 W in a Socket A ceramic PGA package on a 200 MT/s EV6 bus with a 6.5x multiplier at 1.75 V.

A half-ratio lift over the 600 at equal power keeps cooler choice identical, which is why the 650 suited buyers who want a small gain with no thermal change. AMD launched the Socket A 650 on June 5, 2000 with the 600 through 1000 parts. The chip supports MMX and Enhanced 3DNow.

Balanced entry clocks with a full cache suit early Socket A value towers with SDRAM. The 6.5x ratio needs an exact BIOS string. That is why the 650 shipped in mainstream home desktops.

Socket and motherboard compatibility

The 650 fits Socket A early desktops with Thunderbird support. It needs a 462-pin board with a 200 MT/s bus and a BIOS that lists Athlon 650. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Early value towers are the natural match. Boards listing Athlon 650 accept the chip with a 38 W cooler.

Memory, PCIe and cooling

Memory is SDRAM through the board chipset, matched to the board sockets. The CPU has no memory controller. Early boards commonly run PC100 pairs.

A 200 MT/s EV6 bus ties the CPU to the chipset, while AGP and PCI hang off the chipset. No PCIe lanes originate on the die. Cooling uses the Socket 462 lug clip with a 38 W cooler.

Upgrade paths

On the same socket, a move to an Athlon 700 keeps the board for 50 MHz more at 40 W when the support list names it. An Athlon 600 drops 50 MHz at equal power. A Duron 650 with 64 KB cache is a cooler budget option.

A move to Athlon XP needs 266 MT/s paths. The Socket 462 page lists the range for planning.