CPU Comparison
Core i7-3820 vs Core i7-4820K
A side-by-side comparison of specs, performance and value. The Intel Core i7-3820 is a high-end desktop (HEDT) processor based on the Sandy Bridge-E architecture. Released in early 2012, it features 4 cores and 8 threads, operating at a base clock of 3.6 GHz and a turbo boost of 3.8 GHz. Built on a 32nm process, it is part of the LGA 2011 platform, offering quad-channel DDR3 memory support and 40 PCIe 2.0 lanes. Unlike the smaller Sandy Bridge chips, the i7-3820 lacks integrated graphics, requiring a discrete GPU. It features a massive 10MB L3 cache and a 130W TDP. The processor is partially unlocked, allowing multiplier adjustments up to 45x. Though superseded by Ivy Bridge-E, the i7-3820 remains a capable chip for older workstation builds, providing excellent memory bandwidth and PCIe expansion options.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
High clocks and quad-channel memory help with heavy workloads.
Quad-channel memory helps with heavy multitasking.
Gaming
Decent for gaming, but limited by 4 cores compared to modern CPUs.
Still decent for 1080p gaming if overclocked, but lacks modern single-core speed.
Virtualization
Good for VMs, but limited thread count.
Excellent due to VT-d and 40 PCIe lanes.
Efficiency
130W TDP is high for a 4-core chip.
130W TDP for a quad-core is highly inefficient by modern standards.
Specialized Performance
AI / ML
- No AI acceleration
- PCIe 2.0 limits modern AI accelerators
- Can run basic AI models via PCIe GPUs
- No native AI acceleration
Content Creation
Gaming
- High clocks help
- Lacks modern instruction sets
- PCIe 2.0 limits modern GPUs
- High base clock helps older games
- Requires discrete GPU
- Can bottleneck modern high-end GPUs at 1080p
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
Pros
- 40 PCIe 2.0 lanes
- Quad-channel memory
- 10MB L3 cache
- Partially unlocked
Cons
- High 130W TDP
- Only 4 cores
- No integrated graphics
- Obsolete platform
Pros
- Unlocked multiplier
- 40 PCIe lanes
- Quad-channel memory support
- Large 10MB L3 cache
Cons
- Only 4 cores
- High 130W TDP
- No integrated graphics
- Outdated LGA 2011 platform
Competitors & Alternatives
Core i7-3820
- AMD FX-8150Rival
Desktop
- Intel Core i7-2600KRival
Desktop
- Intel Core i7-3930KRival
HEDT
- AMD FX-8350Rival
Desktop
- Compare head-to-headIntel Core i7-2700KRival
Desktop
- Intel Core i7-4820KAlt
Ivy Bridge-E successor with better overclocking.
- Intel Core i7-4930KAlt
Newer Ivy Bridge-E 6-core alternative.
Core i7-4820K
- AMD FX-8350Rival
Desktop
- Compare head-to-headIntel Core i7-4770KRival
Desktop
- Intel Core i7-4930KAlt
6-core alternative on the same platform.
Newer Haswell-E 6-core alternative.
Compare head-to-head- Intel Core i7-3820Alt
Cheaper, older alternative for LGA 2011.
Our Verdict on Each
A solid HEDT processor with great PCIe expansion and memory bandwidth, though limited by its 4 cores.
Best for: Upgrading an old X79 workstation
Read the full reviewA unique entry-point into Intel's HEDT platform, offering excellent overclocking and quad-channel memory, though its 4-core limit shows its age today.
Best for: Upgrading an existing LGA 2011 system.
Read the full reviewFrequently Asked Questions
Which is better, Core i7-3820 or Core i7-4820K?
Based on our editorial ratings, the Core i7-4820K comes out ahead with a score of 8.5/10. That said, the best choice depends on your workload — check the spec and performance breakdown above for gaming, productivity and efficiency differences.
Which is faster for gaming, Core i7-3820 or Core i7-4820K?
For gaming, the Core i7-4820K leads with a gaming performance score of 75/100 among Core i7-3820 and Core i7-4820K.
Do Core i7-3820 and Core i7-4820K use the same socket?
No. They use different sockets (Core i7-3820: LGA 2011, Core i7-4820K: Intel Socket 2011), so each needs a compatible motherboard.
Which is faster in multi-core benchmarks?
The Core i7-4820K posts the highest multi-core benchmark score. Multi-core results: Core i7-3820 (8,500), Core i7-4820K (14,000). Benchmark figures are approximate and workload-dependent.