Intel Core 2 Duo P8600 vs Apple M3 vs Intel Core 2 Duo T6400

Intel Core 2 Duo P8600

The Intel Core 2 Duo P8600 is a dual core processor for laptops. It features 2.4 GHz and a shared level 2 cache of 3 MB. Due to the smaller cache (Core 2 Duo T-Models got usually 6 MB at this clock rate), the TDP is only 25 Watt (instead of the 35 Watt of the T-models).

Due to the relatively high clock speed, modern games (in 2009) should not be limited by the CPU speed (in conjunction with a middle class graphics card). High end gamers should choose a higher clocked Dual Core instead (when using a high end GPU). Compared to the fastest Turion II Ultra M640, the P8600 should be still faster.

The P8600 uses a Penryn (Montevina Update) core that features 2 integer units, 1 floating point unit, 1 load unit, and 1 store unit in a 14-stages long pipeline. Due to the Wide Dynamic Execution Technology, the core is able to simultaneously execute up to four instructions.

The integrated Enhanced Speedstep is able to downclock the core dynamically as low as 1200 MHz to save power (in idle mode).

The Core 2 Duo P8600 can be used in a Socket P socket with 479 pins: Socket P / Micro Flip-Chip Pin Grid Array (Micro-FCPGA) requires 479-pin surface mount Zero Insertion Force (ZIF) socket (mPGA479M socket) or Micro Flip-Chip Ball Grid Array (Micro-FCBGA) for surface mount (479-ball)

Apple M3

The Apple M3 is a system on a chip (SoC) from Apple for notebooks that was introduced in late 2023. It integrates a new 8-core CPU with 4 performance cores with up to 4.06 GHz and 4 efficiency cores running at up to 2.75 GHz. Apple claims that the CPU is up to 20% faster than in the old Apple M2 (3.5 GHz). 

Due to the higher clock speeds and architecture improvements, the processor performance is also significantly better than the M2 in benchmarks (see e.g. Geekbench below) and can keep up with the fastest CPUs in short single-core tests (like the Raptor Lake i9-13950HX).

The M3 also integrates a new graphics adapter with dynamic caching, mesh shading and ray tracing acceleration. According to Apple, it is 20% faster than the GPU in the M2. The chip integrates again 10 GPU cores, but the cheaper variant only offers 8 cores (e.g. in the entry iMac). Furthermore, the GPU only supports 2 displays (an additional 6K60 display to the internal one).

Both GPU and CPU can access the unified memory on the package together. It is still available in 8, 16 and 24 GB variants and offers the same 100 GB/s maximum bandwidth (unlike the Pro models that feature a reduced memory bandwidth). 

The integrated 16-core Neural Engine has also been revised and now offers 18 TOPS peak performance (versus 15.8 TOPS in the M2 but 35 TOPS in the new A17 Pro). The video engine now supports AV1 decoding in hardware. H.264, HEVC and ProRes (RAW) can still be decoded and encoded.

Unfortunately, the integrated wireless network module only supports Wi-Fi 6E (no Wi-Fi 7) and due to the support of only a single external monitor, the chip also has to make do with no Thunderbolt 4 (Thunderbolt 3 / USB 4 support only for up to 40 Gbit/s).

The chip is manufactured on the current 3nm TSMC process (N3B most likely) and contains 25 billion transistors (+25% vs. Apple M2). The 3nm process should also contribute to the excellent efficiency of the chip. Under load, the M3 CPU consumes approximately 20 Watt.

Intel Core 2 Duo T6400

The Intel Core 2 Duo T6400 is an entry level dual core processor for cheap laptops. It is based on the Penryn core but offers only 2 MB level 2 cache and a slow clock speed of 2 GHz. The performance should be sufficient for office and other casual tasks but high level gaming and HD video editing for example could be limited by the CPU performance.