VIA C7-M 795 socket: Socket 479

What the C7-M 795 is

The VIA C7-M 795 is a 2000 MHz single-core mobile processor from June 2005. It runs one Centaur Esther core at 2000 MHz with no turbo, so 1 core gives 1 thread. Cache is 128 KB of L2 with 128 KB of L1 on a 90 nm SOI process. Power is rated at 20 W in a Socket 479 package on a 533 MHz front side bus with a 15x multiplier at up to 1.196 V.

The Socket 479 package with Pentium M bus compatibility lets the 795 drop into 479-pin laptop boards with VIA-aware BIOS strings, which is why it is the only socketed C7 flagship next to soldered NanoBGA2 twins. VIA sold the C7-M 795 from June 1, 2005. The chip supports MMX, SSE through SSE3, NX bit and PadLock with up to 8 PowerSaver states.

Top mobile Esther clocks with a 20 W envelope suit thin Socket 479 laptops with DDR2 memory. The 533 MHz bus matches Dothan-era boards. That is why the 795 shipped in VIA-powered thin laptops.

Socket and motherboard compatibility

The C7-M 795 fits Socket 479 thin laptops with Esther support. It needs a 479-pin board with a 533 MHz bus and a BIOS that lists VIA C7-M parts. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.

Thin DDR2 laptops are the natural match. Boards listing C7-M 795 accept the chip with a 20 W heat pipe assembly. Intel-only 479 boards with no VIA strings may refuse it.

Memory, PCIe and cooling

Memory is DDR2 through the board chipset, matched to the board slots. The CPU has no memory controller. Thin boards commonly run DDR2-533 pairs for 533 MHz parts.

A 533 MT/s front side bus ties the CPU to the chipset, while expansion hangs off the chipset. No PCIe lanes originate on the die. Cooling uses the laptop heat pipe for the exact chassis, rated for 20 W.

Upgrade paths

On the same socket, a Dothan Pentium M 780 at 2260 MHz doubles cache to 2 MB when the support list names it. A C7 2.0 such as VIA C7 2.0 is the soldered NanoBGA2 twin at matching clocks with no replacement path.

A move to VIA Nano needs a NanoBGA2 board. The Socket 479 page lists the Banias to Esther range for planning.