Intel Core 2 Extreme QX9650 socket: LGA 775
The Intel Core 2 Extreme QX9650 uses the LGA 775 socket. It is a 130 W unlocked quad-core Yorkfield desktop part at 3 GHz with 12 MB of L2 cache for enthusiast towers.
- Socket
- LGA 775
- Launched
- November 2007
- Cores and threads
- 4 and 4
- Base power
- 130 W
- Codename
- Yorkfield
- Segment
- Desktop
- Family
- Intel Core 2 Extreme
- Clocks
- 3.0 GHz
Intel Core 2 Extreme QX9650 specifications
| Cores | 4 |
|---|---|
| Threads | 4 |
| Core architecture | Yorkfield XE cores on 45 nm |
| Clocks | 3 GHz (no turbo) |
| Cache | 12 MB L2 (2x6 MB) |
| Processor base power (TDP) | 130 W |
| Manufacturing process | 45 nm |
| Memory support | DDR2 or DDR3 through the board chipset |
| Front side bus | 1333 MT/s |
| PCI Express | PCIe from the board chipset |
| Integrated graphics | None (board video where fitted) |
| Multiplier | Unlocked |
| Package | LGA 775 |
Motherboard and chipset compatibility
Intel Core 2 Extreme QX9650 needs a motherboard with a LGA 775 socket. The table shows which chipset series accept it.
| Series | Chipsets | Support |
|---|---|---|
| Intel 4 series | X48, P45, G45, G41 | Works out of the box |
| Intel 3 series | X38, P35, G33, G31 | Needs a BIOS update 45 nm Yorkfield quads boot on 3 series boards that list them, after a BIOS update. |
Board makers publish a CPU support list for every model. Check it for your exact board before buying. Chipset details for LGA 775.
LGA 775 at a glance
| Type | LGA, 775 contacts |
|---|---|
| Package size | 37.5 × 37.5 mm |
| Introduced | 2004 |
| Memory | DDR, DDR2 or DDR3, depending on the motherboard chipset |
| Cooler mounting holes | 72 × 72 mm |
What the Core 2 Extreme QX9650 is
The Intel Core 2 Extreme QX9650 is a 3 GHz unlocked desktop quad core from November 2007. It runs four Core cores at 3 GHz with no turbo, so 4 cores give 4 threads. Cache is 12 MB of L2 as two 6 MB dies on a 45 nm process. Power is rated at 130 W on LGA 775.
The QX9650 opened the 45 nm Yorkfield XE line on a 1333 MT/s bus in C0 stepping with a 9x unlocked multiplier at about 999 dollars launch price. It exists because enthusiasts wanted a cooler 45 nm unlocked quad with SSE4.1 and larger cache than 65 nm Kentsfield XE.
Socket and motherboard compatibility
The QX9650 drops into LGA 775 enthusiast boards with DDR2 or DDR3 memory and a BIOS that lists late 2007 Yorkfield Extreme quads, such as P35, X38 and 4 series boards. Boards need voltage regulator support for the 130 W envelope. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.
Memory, PCIe and cooling
Memory is DDR2 or DDR3 through the board chipset in two channels, depending on the board.
A 1333 MT/s front side bus ties the CPU to the chipset. PCIe slots hang off the chipset.
Cooling is a 130 W rated LGA 775 tower or high-end heatsink on the 72 mm mount, with Enhanced SpeedStep trimming draw at idle.
Upgrade paths
On LGA 775 the upgrade is the 3.2 GHz QX9770 on a 1600 MT/s bus in the same unlocked Yorkfield class, or the Intel Core 2 Extreme QX6850 at 3 GHz for a 65 nm Extreme. The 2.833 GHz Q9550 drops to a locked multiplier. Beyond LGA 775 a move to a newer platform needs a new board and memory.
Frequently asked questions
What socket does the Core 2 Extreme QX9650 use?
LGA 775, on enthusiast DDR2 or DDR3 boards with Yorkfield Extreme support.
How many cores does the Core 2 Extreme QX9650 have?
Four cores and 4 threads at 3 GHz with 12 MB of L2 cache and an unlocked multiplier.
What memory works with the Core 2 Extreme QX9650?
DDR2 or DDR3 through the board chipset in two channels, depending on the board.
Sources and verification
Facts last checked against these sources on . Page last edited on .