CPU Comparison

Intel Core i5-2400 vs Intel Core i5-2550K

A side-by-side comparison of specs, performance and value. The Intel Core i5-2400 served as the baseline standard-power quad-core processor for the Sandy Bridge generation. Operating at a 95W TDP, it removed the power constraints of the 'S' series, allowing for a higher 3.1 GHz base clock and a 3.4 GHz turbo boost. Like other non-K i5s of its era, it operates without Hyper-Threading, strictly limiting it to four concurrent threads. It features the full 6 MB L3 cache and Intel HD 2000 integrated graphics. This chip was the quintessential mainstream desktop CPU of early 2011, offering a significant leap in IPC (Instructions Per Clock) over the previous Lynnfield architecture.

Intel · Core i5
Intel Core i5-2400
4C / 4T3.4 GHz95 W
5
Full review
Top pick
Intel · Core i5
Intel Core i5-2550K
4C / 4T3.8 GHz95 W
5.5
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Desktop
Desktop
Segment
Desktop
Desktop
Generation
2nd Gen
2nd Gen Core i5 (Sandy Bridge)
Launched
2011
2012
Status
Discontinued
End-of-life
Codename
Sandy Bridge
Sandy Bridge
Series
Core i5
Core i5
Family
Sandy Bridge
Sandy Bridge
Predecessor
Intel Core i5-760
Intel Core i5-2500K
Successor
Intel Core i5-3450
Intel Core i5-3570K

Specifications Compared

Cores & Clocks
Cores
4
4
Threads
4
4
Base Clock
3.1 GHz
3.4 GHz
Boost Clock
3.4 GHz
3.8 GHz
Cache & Power
L3 Cache
6 MB
6 MB
TDP
95 W
95 W
Architecture
Architecture
Sandy Bridge
Sandy Bridge
Process Node
32nm
32nm
Memory
Memory Type
DDR3
DDR3
Memory Speed
DDR3-1333
DDR3-1600
Memory Channels
Dual (2)
Dual (2)
Max Memory
32 GB
32 GB
Platform & I/O
Socket
LGA 1155
LGA 1155
PCIe Version
PCIe 2.0
PCIe 2.0
PCIe Lanes
16
16
Integrated GPU
Yes
None
Unlocked
No
Yes

Performance Compared

Productivity

Intel Core i5-240030

Handles legacy Office suites well, but slow for modern web apps.

Intel Core i5-2550KBest36

Marginally faster than the 2500K in multi-threaded tasks due to 100 MHz higher clocks, but still inadequate for modern software.

Gaming

Intel Core i5-240020

Bottlenecks modern GPUs heavily, but great for pre-2015 games.

Intel Core i5-2550KBest23

The slight clock bump over the 2500K is imperceptible in games. Still completely obsolete for modern titles.

Virtualization

Intel Core i5-2400Best40

Adequate for a basic pfSense router or NAS OS.

Intel Core i5-2550K30

Lacks VT-d, and the lack of an iGPU means no iGPU passthrough, reducing its utility in virtualization setups.

Efficiency

Intel Core i5-2400Best55

Consumes more power per percentage of performance than modern chips.

Intel Core i5-2550K35

Despite the disabled iGPU, power consumption when overclocked is still very high by modern standards.

Specialized Performance

AI / ML

Intel Core i5-2400None
  • No AI acceleration
  • Cannot run modern local LLMs at usable speeds
Intel Core i5-2550KNone
  • No AI hardware
  • Lacks AVX2 and modern instruction extensions
  • Unable to handle any practical AI workload

Content Creation

Intel Core i5-2400Unsupported
Intel Core i5-2550KPoor
Basic Code Compilation

Gaming

Intel Core i5-2400Poor (Modern) / Good (Retro)
  • Paired with a GTX 1060, it can run Skyrim and Fallout 3 excellently
  • Will severely bottleneck anything above an RTX 2060
  • Single-core speed is too low for modern eSports titles like Valorant
Intel Core i5-2550KPoor
  • Virtually identical gaming performance to an overclocked i5-2500K
  • Cannot function without a discrete graphics card
  • Modern games are heavily CPU-limited on this architecture

Industry Impact

Gaming
High
Low
Workstations
Moderate
Negligible
Content Creation
Moderate
Negligible
Virtualization
Moderate
Negligible

Best CPU by Use Case

Retro Gaming
Good
Good
Home Lab Server
Good
Emulation
Good
Modern Gaming
Poor
Overclocking with Discrete GPU
Excellent
CPU Collection
Good
Dedicated Gaming Rig
Poor
Media Encoding without Quick Sync
Poor

Target Audience

Gamers
Targeted
Content Creators
Developers
Workstation Users
Streamers
Office / Productivity
Targeted
Students
Targeted

Strengths & Weaknesses

Intel Core i5-2400

Pros

  • Very cheap on the used market
  • Excellent upgrade path to i7-3770
  • Good retro-gaming performance
  • Easy to cool

Cons

  • No Hyper-Threading
  • No modern instruction set support
  • High power draw relative to performance
  • Locked multiplier
  • Weak HD 2000 graphics
Intel Core i5-2550K

Pros

  • Slightly higher clocks out of the box than the 2500K
  • Unlocked multiplier for easy overclocking
  • Disabled iGPU meant 100% of the die was dedicated to CPU tasks
  • Has become a unique collector's piece
  • No iGPU driver conflicts for pure discrete GPU systems

Cons

  • No integrated graphics whatsoever
  • Lost Intel Quick Sync video encoding
  • More expensive at launch than the 2500K for negligible gains
  • Lacks VT-d
  • No Hyper-Threading

Competitors & Alternatives

Intel Core i5-2400

  • AMD Phenom II X4 970

    Desktop

    Rival
  • AMD FX-4150

    Desktop

    Rival
  • AMD A8-3870K

    Desktop APU

    Rival
  • Rival
    Compare head-to-head
  • Intel Xeon E3-1230

    Server/Workstation

    Rival
  • Better clocks for nearly the same used price.

    Compare head-to-head
  • Intel Core i5-3450
    Alt

    Ivy Bridge upgrade with PCIe 3.0 and lower power.

  • AMD FX-6300
    Alt

    More threads for heavily multi-threaded legacy tasks.

  • Intel Xeon E3-1245
    Alt

    Better integrated graphics and similar performance.

  • Intel Core i7-2600
    Alt

    Adds Hyper-Threading for a significant multi-thread boost.

Intel Core i5-2550K

Our Verdict on Each

An iconic processor that dominated the 2011 market, now best suited for retro gaming builds and lightweight server tasks.

Best for: Building a cheap retro-gaming PC or home server using recycled parts

Read the full review

An intriguing engineering footnote that disabled the iGPU for theoretical overclocking gains, but its minor clock bump and higher price over the 2500K made it one of the least relevant 'K' series processors Intel ever launched.

Best for: Purchasing as a collector's item to complete a Sandy Bridge CPU collection.

Read the full review

Frequently Asked Questions

Which is better, Intel Core i5-2400 or Intel Core i5-2550K?

Based on our editorial ratings, the Intel Core i5-2550K comes out ahead with a score of 5.5/10. 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, Intel Core i5-2400 or Intel Core i5-2550K?

For gaming, the Intel Core i5-2550K leads with a gaming performance score of 23/100 among Intel Core i5-2400 and Intel Core i5-2550K.

Do Intel Core i5-2400 and Intel Core i5-2550K use the same socket?

Yes — all of these CPUs use the LGA 1155 socket, so they share compatible motherboards.

Which is faster in multi-core benchmarks?

The Intel Core i5-2550K posts the highest multi-core benchmark score. Multi-core results: Intel Core i5-2400 (2,800), Intel Core i5-2550K (4,500). Benchmark figures are approximate and workload-dependent.