CPU Comparison
Intel Core i5-1240U vs Intel Core i7-1255U
A side-by-side comparison of specs, performance and value. The Intel Core i5-1240U is an ultra-low power mobile processor from the 12th Generation Alder Lake-U lineup, released in February 2022.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
Handles office tasks and browser tabs well, though burst limits are low.
Highly responsive for daily office tasks, with plenty of E-cores to keep background apps from slowing down the system.
Gaming
Only suitable for 2D or very old 3D games at low resolutions.
Can run esports games like League of Legends smoothly, but struggles with modern AAA titles on integrated graphics.
Virtualization
Can run a light VM, but heavily constrained by the 9W power limit.
Good for light Docker containers, but 2 P-cores limit performance when running full Windows VMs.
Efficiency
Exceptional efficiency, allowing for multi-day battery life in small batteries.
Excellent power management ensures long battery life during typical office use.
Specialized Performance
AI / ML
- Handles basic background blur.
- Not suited for any demanding AI workloads.
- No NPU
- AI workloads handled by CPU/GPU
Content Creation
Gaming
- iGPU is capped at 900 MHz to save power.
- Best for hardware video decoding and simple 2D games.
- Not suitable for 3D gaming.
- Iris Xe 96EU handles 1080p low settings for older games
- Throttles under sustained 3D loads
- Best paired with a discrete GPU for serious gaming
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
Pros
- Exceptional 9W power efficiency
- Allows for silent, fanless designs
- 10 cores for great everyday multitasking
- Supports LPDDR5 memory
- Excellent battery life
Cons
- Very low boost power limit (29W)
- iGPU clocked very low (900 MHz)
- Not suitable for heavy workloads
- Soldered to the motherboard
Pros
- Excellent performance-per-watt
- Very flexible memory support
- Good single-core burst performance
- Plenty of PCIe lanes for an ultrabook chip
- Reliable Iris Xe integrated graphics
Cons
- Only 2 P-cores limit heavy multi-threading
- Soldered to the motherboard
- Can get warm during 55W turbo bursts
- Not suitable for gaming without a discrete GPU
Competitors & Alternatives
Intel Core i5-1240U
- AMD Ryzen 5 5425URival
Mobile
- Compare head-to-headApple M2Rival
Mobile
- Compare head-to-headIntel Core i3-1215URival
Mobile
- Compare head-to-headIntel Core i7-1250URival
Mobile
- Qualcomm Snapdragon 8cx Gen 3Rival
Mobile
Higher base power (15W) for slightly better sustained performance.
Compare head-to-head- Alt
Industry-leading efficiency and performance for fanless designs.
Compare head-to-head - AMD Ryzen 5 6600UAlt
Better iGPU and higher power for standard thin-and-lights.
More threads and higher clocks if you need slightly more power.
Compare head-to-headBudget alternative for basic tasks.
Compare head-to-head
Intel Core i7-1255U
- AMD Ryzen 7 7730URival
Mobile
- AMD Ryzen 7 6800URival
Mobile
- Compare head-to-headApple M2Rival
Mobile
- AMD Ryzen 5 6600URival
Mobile
- Intel Core i7-1185G7Rival
Mobile
Offers slightly higher clock speeds (4.8 GHz) for marginally better burst performance.
Compare head-to-headA more cost-effective alternative that offers very similar everyday performance.
Compare head-to-headBetter sustained performance if you can accommodate the 28W TDP.
Compare head-to-head- AMD Ryzen 7 7735UAlt
Strong alternative with better integrated graphics efficiency.
- Intel Core i7-1355UAlt
The 13th Gen successor with refined efficiency and clock speeds.
Our Verdict on Each
A highly efficient 9W processor that balances 10-core multitasking with extreme battery life, perfect for the most portable form factors.
Best for: Buying an ultra-thin 2-in-1 convertible or a fanless tablet for note-taking and travel.
Read the full reviewA highly efficient and popular 15W processor that powers a vast majority of mid-range premium ultrabooks, offering great daily responsiveness.
Best for: Buying a standard ultrabook for school or office work where you need strong battery life and snappy daily performance.
Read the full reviewFrequently Asked Questions
Which is better, Intel Core i5-1240U or Intel Core i7-1255U?
Based on our editorial ratings, the Intel Core i5-1240U comes out ahead with a score of 8/10. 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 i5-1240U or Intel Core i7-1255U?
For gaming, the Intel Core i7-1255U leads with a gaming performance score of 64/100 among Intel Core i5-1240U and Intel Core i7-1255U.
Which uses less power?
The Intel Core i5-1240U has the lowest rated TDP. Power draw across these chips: Intel Core i5-1240U (9 W), Intel Core i7-1255U (55 W).
Do Intel Core i5-1240U and Intel Core i7-1255U use the same socket?
No. They use different sockets (Intel Core i5-1240U: Intel BGA 1781, Intel Core i7-1255U: Intel BGA 1744), so each needs a compatible motherboard.
Which is faster in multi-core benchmarks?
The Intel Core i7-1255U posts the highest multi-core benchmark score. Multi-core results: Intel Core i7-1255U (0). Benchmark figures are approximate and workload-dependent.