CPU Comparison

The Intel Core i7-4940MX and Intel Processor U300 represent two distinct eras of mobile computing, separated by nearly a decade of architectural evolution. The data shows a fascinating split: the older Haswell part wins in one demanding multi-core workload, while the newer Raptor Lake chip dominates in single-threaded performance and older multi-threaded tests. Their average benchmark scores are nearly identical, 1886 for the i7-4940MX against 1881 for the U300, placing both at the 43rd percentile of all CPUs, yet the way they achieve those scores could not be more different.

Head-to-Head Benchmarks

The most striking result in the head-to-head data is the Cinebench R23 multi-core test, where the Intel Core i7-4940MX delivers a decisive victory. Its score of 5759 beats the Intel Processor U300’s 4905 by a margin of 17.4 percent. This is a notable upset given the U300’s newer architecture and higher boost clock, but it suggests that the i7-4940MX’s eight threads and 8 MB of shared L3 cache are better utilized in this specific workload. The U300, despite having five cores, only has six threads, which may limit its scalability in heavily threaded render tasks.

However, the U300 strikes back forcefully in the Cinebench R23 single-core test. Here, the U300 scores 1616 against the i7-4940MX’s 813, a difference of -49.7 percent from the perspective of the older chip. This means the U300 is nearly twice as fast in single-threaded performance, a gap that reflects the massive IPC improvements from Haswell to Raptor Lake. The U300’s boost clock of 4.40 GHz also plays a role, though the i7-4940MX’s 4.00 GHz boost is respectable for its era.

The Cinebench R15 results reinforce the U300’s dominance in legacy workloads. In the multi-core test, the U300 scores 781 against the i7-4940MX’s 580, a delta of -25.7 percent for the older chip. The single-core R15 test is even more lopsided: the U300 posts 222 while the i7-4940MX manages only 81, representing a -63.5 percent difference. These are the largest deltas in the entire comparison, showing that the U300’s per-core efficiency is overwhelming in this older benchmark suite.

The overall win tally is 3-1 in favor of the Intel Processor U300, but the single win for the i7-4940MX is in the most modern and demanding workload tested. This creates a nuanced picture where the newer chip is generally faster, but the older Extreme Edition processor retains a specific advantage in contemporary multi-threaded rendering.

The Verdict

The benchmark data points to the Intel Processor U300 as the superior choice for most users, but with an important caveat for specific multi-threaded workloads. The U300 wins three out of four head-to-head tests, including both single-core tests by margins of 49.7 percent and 63.5 percent, and the R15 multi-core test by 25.7 percent. Its average benchmark score of 1881 is within 0.3 percent of the i7-4940MX’s 1886, meaning the overall performance level is comparable, but the U300 achieves it with dramatically better efficiency.

The i7-4940MX is the pick for users who prioritize the Cinebench R23 multi-core workload specifically. Its 5759 score is 17.4 percent ahead of the U300, and this is the most modern render test in the dataset. The i7-4940MX also has an unlocked multiplier, allowing overclocking, which could potentially extend its lead in this area. However, its 57 W TDP against the U300’s 15 W TDP means it consumes significantly more power to achieve that result.

For general productivity, the U300 is the clear winner. Its single-core performance is transformative, and its R15 multi-core score of 781 versus 580 shows it handles older software better. The U300 also supports DDR4 and DDR5 memory, while the i7-4940MX is limited to DDR3, giving the newer chip a platform-level advantage that extends beyond raw CPU scores.

The Verdict is straightforward: the Intel Processor U300 is the better all-rounder, while the Intel Core i7-4940MX is a specialist for one specific, albeit modern, multi-threaded benchmark.

Where Each One Wins

The Intel Core i7-4940MX wins in Cinebench R23 multi-core, where its 5759 score outpaces the U300’s 4905 by 17.4 percent. This suggests the i7-4940MX is better suited for modern multi-threaded render workloads that scale well with eight threads and shared L3 cache. The 8 MB of shared L3 cache is identical to the U300, but the i7-4940MX’s four physical cores with Hyper-Threading appear to be more effective in this specific test than the U300’s five cores with only six threads.

The Intel Processor U300 wins in every other measured scenario. In single-core tests, it is nearly twice as fast, which translates to snappier application responsiveness, faster compile times for sequential code, and better performance in lightly threaded games or productivity apps. Its R15 multi-core win by 25.7 percent indicates it also handles legacy software better, which is common for newer architectures that can execute older instructions more efficiently.

The U300’s advantages extend to power efficiency, though the data does not include direct power consumption benchmarks. Its 15 W TDP is 42 W lower than the i7-4940MX’s 57 W TDP, which makes it more suitable for thin-and-light laptops. The U300’s PCIe Gen 4 support with 8 lanes, versus the i7-4940MX’s PCIe Gen 3 with 16 lanes, offers newer connectivity standards, though the older chip has more lanes for multi-GPU setups.

In summary, the i7-4940MX wins only in the most modern multi-core render test, while the U300 wins in single-core, legacy multi-core, and efficiency-driven use cases.

FAQ

Q: Which CPU has a higher average benchmark score?

A: The Intel Core i7-4940MX has a slightly higher average benchmark score of 1886, compared to the Intel Processor U300’s 1881, a difference of 0.3 percent.

Q: How much faster is the Intel Processor U300 in single-core Cinebench R23?

A: The U300 scores 1616 in Cinebench R23 single-core, which is 49.7 percent higher than the i7-4940MX’s score of 813.

Q: In which test does the Intel Core i7-4940MX outperform the U300?

A: The i7-4940MX wins in Cinebench R23 multi-core, scoring 5759 against the U300’s 4905, a margin of 17.4 percent.

Q: What are the core and thread counts for each processor?

A: The i7-4940MX has 4 cores and 8 threads, while the U300 has 5 cores and 6 threads.

Q: What is the TDP difference between the two CPUs?

A: The i7-4940MX has a TDP of 57 W, while the U300 has a TDP of 15 W, making the U300 significantly more power-efficient.

Q: Which processor supports DDR5 memory?

A: The Intel Processor U300 supports DDR4 and DDR5 memory, whereas the Intel Core i7-4940MX only supports DDR3.

Architecture Differences

The architectural gap between these two processors is substantial, spanning multiple generations of Intel design. The Intel Core i7-4940MX is built on the Haswell architecture using a 22 nm process node, fabricated by Intel with 1,400 million transistors on a 177 mm² die. Its codename is Haswell, and it belongs to the Core i7 Extreme generation. The Intel Processor U300 uses the Raptor Lake architecture on a 10 nm process node, also fabricated by Intel, but the transistor count and die size are not listed in the data. Its codename is Raptor Lake-U, and it belongs to the Intel Processor generation.

The core configurations differ significantly. The i7-4940MX has 4 cores and 8 threads, while the U300 has 5 cores and 6 threads. This means the older chip relies on Hyper-Threading to double its thread count, while the newer chip has more physical cores but fewer threads, indicating a hybrid design with efficiency cores that do not support Hyper-Threading. The cache hierarchy also differs: the i7-4940MX has 64 KB of L1 and 256 KB of L2 per core, while the U300 has 80 KB of L1 and 1.25 MB of L2 per core. Both share 8 MB of L3 cache.

Clock speeds tell a story of efficiency improvements. The i7-4940MX has a base clock of 3.10 GHz and a boost clock of 4.00 GHz, while the U300 has a base clock of 1200.00 MHz and a boost clock of 4.40 GHz. The U300’s much lower base clock is typical of hybrid architectures that use low-power efficiency cores for background tasks, while its higher boost clock powers performance cores.

Memory support is another major divergence. The i7-4940MX uses DDR3 memory with a dual-channel bus and a memory bandwidth of 25.6 GB/s. The U300 supports both DDR4 and DDR5, also with a dual-channel bus, but its memory bandwidth is not listed. Neither processor supports ECC memory.

The integrated graphics differ as well. The i7-4940MX includes Intel HD 4600, while the U300 features UHD Graphics 48EU, reflecting a generational leap in iGPU capability. The i7-4940MX uses Intel Socket G3 and has PCIe Gen 3 with 16 lanes from the CPU, while the U300 uses Intel BGA 1744 and has PCIe Gen 4 with 8 lanes. The i7-4940MX has an unlocked multiplier and a part number of SR1PP, while the U300’s multiplier is locked and its part number is SRMLU. The i7-4940MX was released in 2014 and is end-of-life, while the U300 was released in 2023 and is active.