China’s Loongson CPU seems to have IPC equivalent to Zen 4 and Raptor Lake — but slow speeds and limited core count keeps 3A6000 well behind modern competition

Loongson’s 3A6000 CPU, though lacking in raw performance, is actually nearly on par with AMD’s and Intel’s latest architectures in respect to instructions-per-clock, according to Geekwan’s review of the Chinese processor. Though the China-designed 3A6000 is nowhere near the performance level of the latest x86 and Arm CPUs, its high IPC shows promise for future generations of Loongson’s chips, as long as the company can manage higher frequencies.

The 3A6000 uses the LoongArch architecture, an in-house design that has garnered some scrutiny for potentially being a clone of MIPS, which Loongson had formerly used for many years. The chip is fabricated on a 12nm process (probably from China’s SMIC) and has four cores and eight threads capable of boosting to 2.5GHz under a 50 watt TDP. It’s paired with an L2 cache of 256KB and an L3 cache of 16MB, and is compatible with DDR4-3200 memory. The 3A6000 is made for consumer PCs, and in theory competes with the lowest-end CPUs from AMD and Intel.

Given that the 3A6000 has such a low clock speed by today’s standards (even the Pentium Gold G7400 has a boost clock of 3.7GHz), it wasn’t surprising that Geekwan’s benchmarks showed that Loongson’s CPU wasn’t an impressive performer. It couldn’t even catch up to Intel’s 2020-era Core i3-10100, which enjoyed roughly a 20% to 40% performance advantage. Efficiency wasn’t impressive either, as the 3A6000 consumed about 40 watts to the 10100’s 30 or so watts. It’s not a great result for the 3A6000 considering the 10100’s underlying technology is actually from 2016.

On the other hand, the 3A6000 has truly great IPC, or instructions-per-clock. This metric measures performance per clock cycle, and it basically evaluates the performance of the architecture itself. IPC is notoriously difficult to improve, and many designers improve performance by focusing on other specifications, like core count, clock speed, or cache.

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3A6000 SPEC 2017 IPC Comparison
Row 0 – Cell 0 Integer Floating Point
3A6000 4.8 6.0
3A5000 3 3.7
Ryzen 9 7950X 5.0 7.1
Ryzen 9 5950X 4.6 6.6
Core i9-14900K 4.9 7.8

In SPEC 2017’s integer and floating point performance test with all CPUs locked to 2.5GHz (the maximum speed of the 3A6000), Loongson’s chip looks far more potent. It’s actually ahead of the Zen 3-based Ryzen 9 5950X and just barely behind the Zen 4-powered Ryzen 9 7950X and Raptor Lake Core i9-14900K. The comparison isn’t quite as favorable for the 3A6000 in floating point performance, but it is nevertheless quite close. These results corroborate previous benchmarks that showed the 3A6000 packed some impressive IPC.

Loongson is far from being able to compete with modern flagship CPUs from AMD, Intel, Apple, and others. The 3A6000 can’t truly harness its great IPC since it has such a low clock speed, and it’s also lacking quite a bit in core count and cache size. The company’s next-generation 3A7000 may improve on these points, as it’s rumored to use a 7nm process, which may help to boost clock speeds and make more room for more cores and more cache.

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