AMD FX-8350 vs Intel Core i7-8665U Comparison

Head-to-Head Benchmarks

The recorded benchmark data for these two processors does not include any direct head-to-head test results, so the comparison must be built from their respective benchmark suites and aggregate scores. The AMD FX-8350 delivers a Geekbench multicore score of 2551 and a single-core score of 563, while the Intel Core i7-8665U has no Geekbench results in the database. Instead, the Intel part is measured through Cinebench R15, R20, and R23, where it posts multicore scores of 527, 2197, and 5232, respectively, alongside single-core scores of 74, 309, and 738.

Looking at aggregate performance, the FX-8350 holds an average benchmark score of 1557, which places it slightly above the i7-8665U's average of 1513. That difference of 44 points is roughly a 2.9% margin in favor of the AMD part, a narrow gap that aligns with their similar percentile rankings. The FX-8350 sits at the 39th percentile of all CPUs in the database, while the i7-8665U sits at the 38th percentile, indicating both processors land in the same general performance tier despite their very different designs.

The nearest rivals for each processor help contextualize these averages. The FX-8350 performs on par with the Intel Xeon E3-1268L v5, which matches its 1557 average score exactly. It also trades blows with the Intel Core i3-1115G4E, which scores 1559 and sits 0.1% higher, the AMD Opteron 6276 at 1560 (0.2% higher), and the Intel Core i3-9300 at 1554 (0.2% lower). The i7-8665U, meanwhile, is 0.7% behind the Intel Pentium Gold G7400E (1524), 0.9% behind the Intel Core i5-4670S (1526), 0.9% behind the Intel Core i5-7440HQ (1527), and 0.9% ahead of the Intel Core i3-8100T (1500). These comparisons show that both processors cluster among mid-range desktop and mobile chips from several generations, with neither offering a decisive aggregate advantage over its closest competition.

The single-core picture, where the data allows a comparison, is more nuanced. The FX-8350's Geekbench single-core score of 563 is not directly comparable to the i7-8665U's Cinebench single-core results, as the tests measure different workloads and scoring scales. However, within the Cinebench suite, the i7-8665U shows a consistent scaling pattern: its R20 single-core score of 309 is roughly 4.2 times its R15 single-core score of 74, while its R23 single-core score of 738 is roughly 2.4 times the R20 figure. The multicore scaling tells a similar story, with R20 at 2197 being about 4.2 times R15's 527, and R23 at 5232 being about 2.4 times R20. This internal consistency suggests the i7-8665U's performance is stable across Cinebench revisions.

Architecture Differences

The architectural gap between these two processors is substantial. The AMD FX-8350 uses the Piledriver architecture under the Vishera codename, built on a 32 nm process at GlobalFoundries with 1,200 million transistors on a 315 mm² die. It is an eight-core, eight-thread desktop part with a 4.00 GHz base clock and 4.20 GHz boost clock. The Intel Core i7-8665U, in contrast, uses the Whiskey Lake architecture under the Whiskey Lake-U codename, built on a 14 nm process at Intel. It is a four-core, eight-thread mobile part with a base clock of 1900.00 MHz and a boost clock of 4.80 GHz. The FX-8350's clock speeds are higher at the base level, but the i7-8665U's boost clock of 4.80 GHz exceeds the AMD part's 4.20 GHz maximum.

Cache layouts differ as well. The FX-8350 has 384 KB of L1 cache, 8 MB of L2 cache, and 8 MB of shared L3 cache. The i7-8665U specifies its cache on a per-core basis: 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3. With four cores, the Intel part's total L1 is 256 KB and total L2 is 1 MB, both well below the FX-8350's aggregate cache. The shared L3 is identical at 8 MB, however, meaning the two processors match on the final cache tier.

Memory support also diverges. The FX-8350 supports DDR3 memory over a dual-channel bus with a peak bandwidth of 29.9 GB/s. The i7-8665U supports both DDR3 and DDR4, also over a dual-channel bus, with a higher peak bandwidth of 38.4 GB/s. Neither processor supports ECC memory. The PCIe interface differs by one generation: the FX-8350 uses PCIe Gen 2, while the i7-8665U uses PCIe Gen 3 with 16 lanes available from the CPU. Integrated graphics are handled differently, with the FX-8350 relying on certain motherboards as a chipset feature, while the i7-8665U includes UHD Graphics 620 directly on the processor.

Power and packaging are starkly different. The FX-8350 has a TDP of 125 watts and uses the AMD Socket AM3+, while the i7-8665U has a TDP of 15 watts and uses the Intel BGA 1528 socket. This eightfold difference in TDP explains the form factor split: the FX-8350 is a desktop part, and the i7-8665U is a mobile part. The FX-8350 also has an unlocked multiplier, enabling overclocking, whereas the i7-8665U has a locked multiplier. The FX-8350's launch MSRP was $199, and the i7-8665U's launch MSRP was $409.

Where Each One Wins

The data suggests a clear use-case split based on where each processor's strengths lie. The FX-8350's higher average benchmark score of 1557 versus 1513 gives it a slight overall edge in the database's aggregate metric, but the more meaningful distinction comes from workload type and platform context.

The FX-8350 wins on raw core count and thread count, offering eight physical cores and eight threads against the i7-8665U's four cores and eight threads. For workloads that scale with physical cores, such as heavily threaded desktop applications, the AMD part has a structural advantage. Its 125 W TDP and desktop socket also indicate it is designed for sustained, high-power operation, which is beneficial for long-running compute tasks. The unlocked multiplier is another point in its favor, as it allows users to push clock speeds beyond the stock 4.20 GHz boost, something the locked i7-8665U cannot do. Its 8 MB of L2 cache, compared to roughly 1 MB total on the Intel part, also favors workloads with high cache reuse.

The i7-8665U wins on efficiency and mobility. Its 15 W TDP is a fraction of the FX-8350's 125 W, making it suitable for thin-and-light laptops where power draw and heat dissipation are critical constraints. Its 4.80 GHz boost clock is higher than the FX-8350's 4.20 GHz, giving it a peak single-thread speed advantage that benefits lightly threaded workloads like web browsing, office productivity, and everyday responsiveness. The integrated UHD Graphics 620 means it can handle display output and basic graphics acceleration without a discrete GPU, which is impossible on the FX-8350 without a motherboard chipset feature. Its support for DDR4 memory and PCIe Gen 3 also gives it access to more modern platform features, including the higher 38.4 GB/s memory bandwidth.

In benchmark terms, the i7-8665U's Cinebench R23 multicore score of 5232 demonstrates that a four-core, eight-thread mobile chip can deliver competitive rendering performance within its power envelope. The FX-8350's Geekbench multicore score of 2551, while not directly comparable, places it firmly in the desktop mid-range. The percentile rankings tell the broader story: both processors are near the middle of the database, with the FX-8350 at the 39th percentile and the i7-8665U at the 38th percentile, so neither is positioned as a high-end performer in its respective market.

Specification Differences

The two processors differ across nearly every specification field in the database. The FX-8350 has 8 cores and 8 threads, while the i7-8665U has 4 cores and 8 threads. Base clocks are 4.00 GHz for the AMD part and 1900.00 MHz for the Intel part, and boost clocks are 4.20 GHz and 4.80 GHz, respectively. The TDP figures are 125 watts and 15 watts. The FX-8350 uses the AMD Socket AM3+, while the i7-8665U uses the Intel BGA 1528. The architectures are Piledriver versus Whiskey Lake, with codenames Vishera and Whiskey Lake-U. The process nodes are 32 nm at GlobalFoundries versus 14 nm at Intel. The FX-8350 lists 1,200 million transistors and a 315 mm² die size, while the i7-8665U has no transistor or die size data in the database.

Cache configurations differ in L1 and L2. The FX-8350 has 384 KB of L1 and 8 MB of L2, while the i7-8665U has 64 KB per core of L1 and 256 KB per core of L2. Both have 8 MB of shared L3. Memory support is DDR3 for the AMD part and DDR3 or DDR4 for the Intel part, with memory bandwidths of 29.9 GB/s and 38.4 GB/s, respectively. Both use dual-channel memory buses. PCIe support is Gen 2 on the FX-8350 and Gen 3 with 16 CPU lanes on the i7-8665U. The FX-8350's integrated graphics are a chipset feature on certain motherboards, while the i7-8665U has UHD Graphics 620. The market segments are Desktop and Mobile. Both processors are end-of-life. The FX-8350 was released on 2012-10-22, and the i7-8665U was released on 2018-09-30. The launch MSRP values are $199 and $409, respectively. The FX-8350 has an unlocked multiplier, while the i7-8665U's multiplier is locked. Part numbers are FD8350FRW8KHKFD8350FRHKBOX and SRF9W.

FAQ

Q: Which processor has the higher average benchmark score?

A: The AMD FX-8350 has an average benchmark score of 1557, which is 44 points higher than the Intel Core i7-8665U's average of 1513.

Q: How do their percentile rankings compare?

A: The FX-8350 is at the 39th percentile of all CPUs in the database, while the i7-8665U is at the 38th percentile, a difference of one percentile point.

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

A: The FX-8350 has 8 cores and 8 threads, while the i7-8665U has 4 cores and 8 threads.

Q: How do the boost clocks compare?

A: The FX-8350 has a boost clock of 4.20 GHz, while the i7-8665U has a higher boost clock of 4.80 GHz.

Q: What is the TDP difference between the two?

A: The FX-8350 has a TDP of 125 watts, and the i7-8665U has a TDP of 15 watts, making the Intel part far more power-efficient.

Q: Do both processors support ECC memory?

A: No, neither processor supports ECC memory.

Q: Which processor has an unlocked multiplier?

A: The AMD FX-8350 has an unlocked multiplier, while the Intel Core i7-8665U does not.