Intel Core 2 Extreme QX9770
Drops into a supported LGA 775 board as it is; check the board's CPU list. How to check.
Intel Core 2 Extreme QX9770: 4-core, 3.2 GHz, Yorkfield, LGA 775, 1600 MT/s FSB, 12 MB (2 x 6 MB) L2, 136 W TDP.
The QX9770 is the only LGA 775 chip in this database rated for a 1600 MT/s bus: a 400 MHz bus clock times 8 gives 3.2 GHz. Its 136 W TDP is an odd figure, a notch above the QX9650, and its Tcase of 55.5 °C is the lowest of any chip here, so it has less thermal headroom than its siblings. Cool it generously. The L2 is the full Yorkfield 12 MB in two 6 MB halves, with SSE4.1 and VT-x. C1 (SLAWM, CPUID 10677) is covered by Intel's spec update. The C0 sSpec SLAN2 is not; CPU-World confirms its model, clock, bus and socket, and its CPUID, 10676, comes from the stepping table.
| Family | Core 2 Extreme |
|---|---|
| Codename | Yorkfield |
| Socket | LGA 775 |
| Cores / threads | 4 / 4 |
| Base clock | 3.2 GHz |
| Front-side bus | 1600 MT/s (400 MHz base clock) |
| Multiplier | 8x |
| L2 cache | 12 MB (2 x 6 MB) |
| TDP | 136 W |
| Process | 45 nm |
| Launch | Q1 2008 |
| Dual-socket capable | No |
| VT-x | Yes |
| SSE4.1 | Yes |
| Enhanced SpeedStep | Yes |
| Max case temperature | 55.5 °C |
| Voltage range (VID) | 0.85 V to 1.3625 V |
Steppings and microcode IDs
| Stepping | CPUID | sSpec |
|---|---|---|
| C0 | 10676 | SLAN2 |
| C1 | 10677 | SLAWM |
A BIOS needs a microcode update matching the CPUID (and, for Xeons, the LGA 771 platform ID). See LGA 771 Xeon microcode and how to read your stepping.
Mod notes
The board must run a 400 MHz bus (1600 MT/s) and list the QX9770 by stepping; on a board that cannot, the chip runs slower than rated. It also wants power delivery sized for 136 W, so check the CPU support list and the BIOS version that adds it before you settle on a board.