Intel Core i7-6700K socket: LGA 1151
The Intel Core i7-6700K uses the LGA 1151 socket on revision 1 boards. It is the 4-core 8-thread Skylake flagship that opened the socket in 2015, on 100 series boards and later 200 series boards.
- Socket
- LGA 1151
- Launched
- August 2015
- Cores and threads
- 4 and 8
- Base power
- 91 W
- Codename
- Skylake
- Segment
- Desktop
- Family
- Intel Core i7
- Clocks
- 4.0 / 4.2 GHz
Intel Core i7-6700K specifications
| Cores | 4 |
|---|---|
| Threads | 8 |
| Core architecture | Skylake based cores on 14 nm |
| Clocks | 4.0 GHz base, up to 4.2 GHz (Turbo Boost 2.0) |
| Cache | 8 MB Intel Smart Cache (L3) |
| Processor base power (TDP) | 91 W |
| Manufacturing process | 14 nm |
| Memory support | DDR4 up to 2133 MT/s (DDR3L up to 1600 MT/s on some boards), two channels, up to 64 GB |
| PCI Express | 16 lanes from the CPU, PCIe 3.0 |
| Integrated graphics | Intel HD Graphics 530 (up to 1.15 GHz) |
| Multiplier | Unlocked (K series) |
| Package | FCLGA1151 |
| Cooler in the box | None |
| ECC memory | Not supported |
| Launch price | $350 (Intel RCP) |
Motherboard and chipset compatibility
Intel Core i7-6700K needs a motherboard with a LGA 1151 socket. The table shows which chipset series accept it.
| Series | Chipsets | Support |
|---|---|---|
| 300 series: B365 and Z390 | Z390, B365 | Not supported |
| 300 series: H310, B360, H370, Q370, Z370 | Z370, H370, B360, H310, Q370 | Not supported |
| 200 series | Z270, H270, B250, Q270, Q250 | Works out of the box |
| 100 series | Z170, H170, B150, H110, Q170, Q150 | Works out of the box |
Board makers publish a CPU support list for every model. Check it for your exact board before buying. Chipset details for LGA 1151.
Recommended GPU pairing
| Recommended tier | Mid-range 1080p |
|---|---|
| Example GPUs | GeForce GTX 970, Radeon R9 390 |
| Target resolution | 1080p high settings |
Four threaded cores with boost to 4.2 GHz, 16 PCIe 3.0 lanes and DDR4 line up with mid-range 1080p cards from 2015. A faster card still works and the balance shifts with game, settings and resolution.
This is a rough match for a new build at the stated resolution, not a limit. A faster card still works and helps at higher resolutions or in games that load the GPU more than the CPU. A slower card is fine for lighter games and office use. The exact balance shifts with the game, the settings and the resolution, so no percentage is given.
LGA 1151 at a glance
| Type | LGA, 1,151 contacts |
|---|---|
| Package size | 37.5 × 37.5 mm |
| Introduced | August 2015 |
| Memory | DDR4 on most boards (some early boards use DDR3L). DDR4 only on the second revision |
| Cooler mounting holes | 75 × 75 mm |
What the Core i7-6700K is
The Core i7-6700K is a four core, eight thread processor that Intel released in August 2015 as the Skylake desktop flagship. Its cores run 4.0 GHz base to 4.2 GHz turbo with Turbo Boost 2.0. Cache is 8 MB of shared L3.
Skylake brought DDR4 to the mainstream platform alongside Hyper-Threading on the i7, with a 4.0 GHz base clock that was high for its day. The TDP is 91 W on the 14 nm process.
Intel HD Graphics 530 handle display output, at up to 1.15 GHz. The multiplier is unlocked. The launch price was $350 (Intel RCP). Intel includes no cooler with K-series processors.
Socket and motherboard compatibility
The 6700K fits the LGA 1151 socket on revision 1 boards. Z170, H170, B150, H110, Q170 and Q150 boards accept it natively. Later 200 series boards accept Skylake chips as well. Revision 2 boards with 300 series chipsets never support it.
A Z170 or Z270 board unlocks the multiplier. Other chipsets hold rated clocks with memory tuning on most models.
DDR3L boards need DDR3L memory at 1.35 V, never standard DDR3 at 1.5 V, which damages the processor over time. DDR4 boards need DDR4 instead.
Memory, PCIe and cooling
The memory controller supports DDR4 up to 2133 MT/s, with DDR3L up to 1600 MT/s possible on boards built with DDR3L slots instead. Two channels carry up to 64 GB. ECC memory is not supported.
The CPU supplies 16 PCIe 3.0 lanes from the processor. Chipset lanes cover the remaining slots and drives at lower speeds.
Cooling should exceed the 91 W base rating under boost. Plan a capable tower cooler on the 75 mm LGA 1151 pattern. The CPU cooler compatibility by socket guide lists bracket requirements.
The chip that opened LGA 1151
The 6700K opened the LGA 1151 era with DDR4, Hyper-Threading, and an unlocked multiplier on the i7. Its combination of DDR4, threading, and an unlocked multiplier covered gaming and creation alike. The 4.0 GHz base clock was high for its day, so lightly threaded work rarely waited on frequency.
The revision split came later but applies in hindsight: revision 1 boards take it, while revision 2 boards with 300 series chipsets never accept it despite the identical socket. Within revision 1 the upgrade path runs to the Kaby Lake i7 on 200 series boards or updated 100 series boards.
Upgrade paths
Against the Intel Core i7-7700K, the 6700K trades clocks and media features on the same socket, subject to BIOS. Against the Intel Core i7-8700K, it gives up two cores on an older platform.
Moving to LGA 1200 needs a new board while keeping DDR4. The 6700K fits a Z170 gaming PC from the start of the DDR4 era.
Frequently asked questions
What socket does the Intel Core i7-6700K use?
It uses LGA 1151 on revision 1 boards with 100 or 200 series chipsets, written FCLGA1151 in Intel's documents.
What is the difference between the 6700K and the 7700K?
The 6700K is a Skylake chip with HD 530 graphics and DDR4-2133 support, while the 7700K is a Kaby Lake chip with HD 630 graphics and DDR4-2400 support.
Does the 6700K run in a Z270 motherboard?
Yes. Z270 and other 200 series boards accept Skylake processors. Only 300 series boards never support them.
Does the 6700K work with DDR3 memory?
Yes, on a board with DDR3L slots, at 1.35 V. Standard 1.5 V DDR3 damages the processor and must not be used.
Does the 6700K come with a cooler?
No. K-series processors ship without a cooler, and 91 W peaks need a capable tower cooler for sustained loads.
Sources and verification
Facts last checked against these sources on . Page last edited on .