Intel Core i7-5820K socket: LGA 2011-v3

What the Core i7-5820K is

The Core i7-5820K is the entry Haswell-E six core for HEDT builds on LGA 2011-v3. Intel set six cores and 12 threads at 3.3 GHz base with turbo to 3.6 GHz. Fifteen megabytes of Smart Cache serve renders and compiles. Power is 140 W on 22 nm from September 2014. It brings DDR4 and extra lanes to buyers who need more than mainstream LGA 1150.

Six threads beyond quads cut parallel task times in editing and 3D work. At 3.3 GHz with bursts to 3.6 GHz, single thread pace trails fast quads but multi thread throughput leads by a wide margin. The unlocked multiplier allows tuning on X99 with strong cooling. Builders pair it with discrete graphics, since HEDT carries no integrated GPU. Quad channel DDR4 lifts bandwidth for large scenes.

Twenty eight PCIe 3.0 lanes from the CPU feed graphics and NVMe storage, fewer than the 40 lanes on higher HEDT parts. The split still covers two graphics cards plus fast drives on most X99 boards. The 5820K is the value HEDT socket for creators who want cores and lanes without flagship cost.

Socket and motherboard compatibility

The 5820K fits LGA 2011-v3 on X99 boards with Haswell-E firmware. X99 launched with Haswell-E in August 2014, so boards accept it from shipping BIOS. Check the maker CPU list for the minimum version on early stock. LGA 2011 boards never accept Haswell-E despite similar pin counts.

Memory is DDR4 in four channels. The Socket vs chipset: what decides whether a CPU works guide is desktop focused, so use X99 manuals for lane splits. Cooler mounting is 80 × 80 mm from the CPU cooler compatibility by socket guide with towers rated for 140 W. No cooler ships in the box.

A move to Broadwell-E on the same socket needs a BIOS update with new microcode on early boards. Check support before buying a used upgrade.

Memory, PCIe and cooling

DDR4-2133 in quad channel is the memory target, with up to 64 GB on typical HEDT boards and higher on workstation class X99. Four matched sticks unlock full bandwidth for renders. Faster DDR4 kits run through XMP on X99 per manual. ECC is not supported on Core i7 HEDT parts.

PCIe is 28 lanes of PCIe 3.0 from the CPU in 1x16 plus 1x8 plus 1x4 splits for graphics and NVMe. Two graphics cards plus a fast SSD fit without the lane sharing limits of mainstream boards. X99 adds chipset lanes for SATA and USB. Board manuals show exact sharing with M.2 slots.

Cooling needs a large tower or liquid unit for 140 W sustained loads. At 3.3 GHz base with all core turbo, heat rises quickly in closed cases. Keep front to back airflow over the VRM and memory for steady exports.

Upgrade paths

Within the socket the Intel Core i7-5930K at 3.5 GHz to 3.7 GHz with 40 lanes is the lane step for multi GPU rigs on the same X99 boards. The Intel Core i7-4790K on LGA 1150 is a mainstream alternative with higher clocks but fewer cores and lanes. Both need board and memory checks, since DDR3 never fits X99.

A newer HEDT generation means a new socket such as LGA 2066. The 5820K covers value creators who need six cores with DDR4.