Core i7-1255U Vs Core i5-1335U: Should You Upgrade?

Previously, I compared the Core i7-1255U to the Core i5-1235U and discovered a 12.4% and 5.2% difference in multi-core and single-core performance, respectively. This article will put the slightly upgraded 13th gen Core i5 to the same Core i7, in Core i7-1255U vs Core i5-1335U. Read on to find out if the Raptor Lake Core i5 stands a better chance.

Key Takeaways

• The Core i5-1335U outperformed the Core i7-1255U by 14.7% in multi-core applications and 1.6% in single-core applications. In 3DMark Time Spy and HWBOT x265 tests, the Core i7-1255U was 4.1% and 1% faster, respectively.
• Talking power draw, the Core i7-1255U produced 33.3% more heat under load than the Core i5-1335U. 
• As for prices, the Core i7-1255U laptops range from $489 to $4629, while the Core i5-1335U laptops are in the $649-$1894 price bracket.
• Overall, the Core i7-1255U provides more performance per dollar as it’s much cheaper at a fraction of the price difference.

Comparison Table

Let’s compare the specifications of the two CPUs to trace the similarities and differences.

Core i7-1255U vs Core i5-1335U

Here’s an overview of the architectural differences.

Architectural Differences

• Clock Speeds: The Core i7-1255U clocks 1.7GHz on the P-cores and 1.2GHz on the E-cores at base. Conversely, the Core i5-1335U has frequencies of 1.3GHz (P-cores) and 0.9 GHz (E-cores). As for boost speeds, the Core i7-1255U P-cores push up to 4.7GHz and the E-cores up to 3.5GHz. The Core i5-1335U boosts to 4.6GHz (P-cores) and 3.4GHz (E-cores).
• Memory: The Core i5-1335U improves DDR5 (up to 5200 MT/s over 4800 MT/s) and LPDDR5 (up to 6400 MT/s over 5200 MT/s) support. It also adds LPDDR5x support which the Core i7-1255U does not support. 
• Cache: The Intel Core i7-1255U has 18MB of shared L3 Cache, while the Core i5-1335U has 12MB of it.

Also Read: Core i7-12700H Vs Core i7-1255U

Performance: Core i7-1255U Vs Core i5-1335U

I’ve compared the two CPUs in performance in various applications to find the better CPU.

Cinebench R15

• Beginning the proceedings with Cinebench R15, the Core i5-1335U scores 1494 points in the multi-core test. In response, the Core i7-1255U accumulated 1400 points.
• In the single-core test, the Core i7-1255U led with 238.5 points, while the Core i5-1335U managed 231 points. 

Cinebench R23

• Moving on to Cinebench R23, the Core i5-1335U scored 8349 points, just marginally ahead of the Core i7-1255U’s 8332-point tally.
• As for the single-core scores, the Core i7-1255U leads again with 1656 points over 1625 of the Core i5-1335U.

Geekbench 5

• The next test is Geekbench 5, where the Core i5-1335U bagged another win in multi-core performance, with 7984 points. In response, the Core i7-1255U scored 7294 points. 
• The single-core results saw the Core i5-1335U scoring 1637 points compared to 1610 of the Core i7-1255U.

Related: Core i7-1255U Vs Core i7-1165G7

Passmark

• In Passmark, the Core i5-1335U notched up 17057 points, leading the Core i7-1255U’s score of 13905 points.
• Regarding single-core scores, the Core i5-1335U’s tally is 3505 points, while the Core i7-1255U’s figures read 3382 points. 

Summarizing The Multi-Core And Single-Core Performance

Before moving on, I averaged the multi-core and single-core across the four tested applications.

• Multi-core Performance: Overall, the Core i5-1335U accumulated 8721 points while the Core i7-1255U averaged 7597 points. So, on average, the Core i5-1335U is 14.7% faster in multi-core applications.
• Single-core Performance: The Core i5-1335U averaged 1749 points across the four tests, bettering the Core i7-1255U’s score of 1721 points. Thus, the Core i5-1335U is about 1.6% faster than the Core i7-1255U in single-core applications.

Learn: How To Benchmark Your PC/Laptop

3DMark Time Spy CPU Benchmark

• In the 3DMark Time Spy benchmark, the Core i7-1255U proved superior with 6140 points. In reply, the Core i5-1335U scored 5894 points. In exact, the Core i7-1255U performed 4.1% better.

Blender 3.3 Classroom

• The next benchmark is the Blender Classroom render, in which the Core i5-1335U rendered the scene 10 seconds faster than the Core i7-1255U — or 1.4% faster.

Also Read: How Much RAM Do You Need For Video Editing?

HWBOT x265 Benchmark V2.2

• Wrapping up the benchmarks, the Core i7-1255U outscored its Intel Core i5 competitor by just .1 FPS — or 1%.

Power Consumption

Lastly, we’ll look at the average power consumption numbers.

Reminder: Both CPUs have the same base (12-15W) and boost (55W) power ratings.

• Idle power consumption: At idle, the Core i7-1255U averaged 6.2 watts of power consumption, almost double that of the Core i5-1335U’s figure of 3.3 watts. 
• Load power consumption: Under load, the Core i7-1255U used 55.6 watts of power on average, and the Core i5-1335U used 41.7 watts. This makes the Core i5-1335U 33.3% more power-efficient under load.

Laptop Prices 

Wondering how much the laptops cost? I’ve got you covered.

Note: The prices have been estimated from Amazon US and are valid as of August 2023. 

• Core i7-1255U: Entry-level laptops start from $489, while the most popular options are in the $699 to $1257 bracket. These laptops can go as high as $4629.
• Core i5-1335U: Laptops using this mobile CPU cost $649 at the minimum, while the best-sellers will cost you between $665 and $1029. The most expensive laptops go as high as $1894.

Also Read: How Long Do Laptops Last?

Better Value: Core i5-1335U Vs Core i7-1255U

So which CPU has more value? The Core i5-1355U performed 14.7% faster in the multi-core test and 1.6% faster in the single-core tests. It also won the Blender render test. In the remaining tests, the Core i7-1255U performed better but by a narrow margin.

When we look at the prices, there is a 32.7% difference in entry-level laptop prices between the two CPUs. The price difference is greater than the performance difference.

So, the Core i7-1255U has a better performance-per-dollar ratio than the Core i5-1335U.

Final Thoughts 

This marks the end of this comparison. Despite mostly matching specifications, the Core i5-1335U comprehensively outperformed the Core i7-1255U in multi-core applications.

In single-core applications, the gap between the two CPUs was much less, and the same goes for 3DMark Time Spy, Blender, and HWBOT x265 tests. The price difference overpowered all the performance differences, giving Intel’s Core i7-1255U the value crown. 

Remember, though, that with the Core i7-1255U, you’ll be dealing with more power consumption and potentially higher chances of thermal throttling. Additionally, the memory support of the Core i7-1255U is not as good as the Core i5-1355U. 

Pros And Cons 

Pros And Cons: Core i7-1255U vs Core i5-1335U