CPU Comparison

Intel Core i5-1235U vs Intel Core i5-2540M

A side-by-side comparison of specs, performance and value. The Intel Core i5-1235U is a low-power mobile processor from the 12th Generation Alder Lake-U family, launched in February 2022.

Top pick
Intel · Core i5
Intel Core i5-1235U
10C / 12T4.4 GHz15 W
8.2
Full review
Intel · Core i5
Intel Core i5-2540M
2C / 4T3.3 GHz35 W
5.5
Full review

The Bottom Line

Overview & Launch

Brand
Intel
Intel
Market
Mobile
Mobile
Segment
Thin & Light / Everyday
Mobile
Generation
12th Gen
2nd Gen Core i5 (Sandy Bridge)
Launched
2022
2011
Status
Active
End-of-life
Codename
Alder Lake-U
Sandy Bridge
Series
Core i5
Core i5
Family
Alder Lake-U
Sandy Bridge
Predecessor
Intel Core i5-1135G7
Intel Core i5-560M
Successor
Intel Core i5-1335U
Intel Core i5-3210M

Specifications Compared

Cores & Clocks
Cores
10
2
Threads
12
4
Base Clock
1.3 GHz
2.6 GHz
Boost Clock
4.4 GHz
3.3 GHz
Cache & Power
L3 Cache
12 MB
3 MB
TDP
15 W
35 W
Architecture
Architecture
Alder Lake-U
Sandy Bridge
Process Node
10 nm
32nm
Memory
Memory Type
DDR4, DDR5, LPDDR4x, LPDDR5
DDR3
Memory Speed
DDR4-3200, DDR5-4800, LPDDR4x-4267, LPDDR5-5200
DDR3-1333
Memory Channels
Dual (2)
Dual (2)
Max Memory
64 GB
16 GB
Platform & I/O
Socket
Intel BGA 1744
Intel Socket G2 (988B)
PCIe Version
PCIe 4.0
PCIe 2.0
PCIe Lanes
20
16
Integrated GPU
Yes
Yes
Unlocked
No
No

Performance Compared

Productivity

Intel Core i5-1235UBest80

Handles office tasks and heavy browser tabs effortlessly.

Intel Core i5-2540M35

Handles basic office tasks but struggles with large spreadsheets, heavy documents, or multitasking with many browser tabs.

Gaming

Intel Core i5-1235UBest45

Only suitable for very light or older 2D games.

Intel Core i5-2540M15

Cannot run modern AAA titles. Only suitable for very old or lightweight games at low resolutions.

Virtualization

Intel Core i5-1235UBest50

Can run a light VM, but core count is low for heavy dev work.

Intel Core i5-2540M20

Can run a single lightweight VM but lacks the cores and memory bandwidth for serious virtualization.

Efficiency

Intel Core i5-1235UBest95

Top-tier efficiency, allowing for all-day battery life in ultrabooks.

Intel Core i5-2540M25

35 W TDP is high by modern mobile standards; current chips deliver far more performance per watt.

Specialized Performance

AI / ML

Intel Core i5-1235ULow
  • Handles background blur and basic audio enhancement.
  • Not suited for AI development or inference.
Intel Core i5-2540MNone
  • No AI acceleration instructions
  • No NPU or matrix multiplication support
  • Cannot run modern AI workloads

Content Creation

Intel Core i5-1235UModerate
Basic PhotoshopWeb Graphic DesignAudio Editing
Intel Core i5-2540MVery Poor
Basic Photo EditingLight Word Processing

Gaming

Intel Core i5-1235ULow
  • Iris Xe 80EU is sufficient for hardware video decoding.
  • Not recommended for 3D gaming.
  • Can handle Minecraft or CS:GO at low settings.
Intel Core i5-2540MVery Poor
  • Intel HD 3000 lacks modern API support
  • No DirectX 12 or Vulkan support
  • Only playable with pre-2012 titles at low settings

Industry Impact

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

Best CPU by Use Case

Web Browsing
Excellent
Adequate with modern light browsers
Office Applications
Excellent
Video Streaming
Excellent
Light Coding
Very Good
Document Editing
Adequate
Video Playback
Adequate for 1080p with hardware decoding
Light Gaming
Very Limited
Software Development
Limited

Target Audience

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

Strengths & Weaknesses

Intel Core i5-1235U

Pros

  • Excellent power efficiency (15W base TDP)
  • 10 cores provide great multitasking
  • Supports fast LPDDR5 memory
  • Good single-core burst performance
  • Hardware AV1 decoding

Cons

  • Only 2 P-cores limit heavy workloads
  • Basic integrated graphics
  • Locked multiplier
  • Soldered to the motherboard
Intel Core i5-2540M

Pros

  • AES-NI hardware encryption support
  • Reliable and well-tested platform
  • Widely available as spare parts
  • Intel HD 3000 was a meaningful graphics improvement for its era
  • VT-x and VT-d virtualization support

Cons

  • Only 2 cores and 4 threads
  • No DirectX 12 or modern graphics API support
  • 35 W TDP is high for the performance delivered
  • Maximum 16 GB DDR3 memory support
  • Completely obsolete for any modern demanding workload

Competitors & Alternatives

Intel Core i5-1235U

Intel Core i5-2540M

Our Verdict on Each

A highly efficient 15W processor that brings 10-core hybrid architecture to mainstream laptops, offering excellent battery life and solid daily performance.

Best for: Buying a thin-and-light laptop for school, office work, or general everyday use.

Read the full review

The i5-2540M was a solid mid-range mobile chip in 2011, but it is now thoroughly outclassed by modern processors in every metric including efficiency, single-thread speed, and integrated graphics capability.

Best for: Upgrading an existing Socket G2 laptop at minimal cost

Read the full review

Frequently Asked Questions

Which is better, Intel Core i5-1235U or Intel Core i5-2540M?

Based on our editorial ratings, the Intel Core i5-1235U comes out ahead with a score of 8.2/10. 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 i5-1235U or Intel Core i5-2540M?

For gaming, the Intel Core i5-1235U leads with a gaming performance score of 45/100 among Intel Core i5-1235U and Intel Core i5-2540M.

Which uses less power?

The Intel Core i5-1235U has the lowest rated TDP. Power draw across these chips: Intel Core i5-1235U (15 W), Intel Core i5-2540M (35 W).

Do Intel Core i5-1235U and Intel Core i5-2540M use the same socket?

No. They use different sockets (Intel Core i5-1235U: Intel BGA 1744, Intel Core i5-2540M: Intel Socket G2 (988B)), so each needs a compatible motherboard.

Which has more cores?

The Intel Core i5-1235U has the most cores. Core counts: Intel Core i5-1235U (10 cores), Intel Core i5-2540M (2 cores).

Which is faster in multi-core benchmarks?

The Intel Core i5-2540M posts the highest multi-core benchmark score. Multi-core results: Intel Core i5-2540M (3,800). Benchmark figures are approximate and workload-dependent.