Closes #49: Add Raspberry Pi 400.

README.md

@@ -138,6 +138,7 @@ Here are a few of the results I've acquired in my testing (sorted by efficiency,
 | [Ampere Altra Max M128-30 @ 3.0 GHz](https://github.com/geerlingguy/top500-benchmark/issues/3) | Arm | 953.47 Gflops | 500W | 1.91 Gflops/W |
 | [Turing Pi 2 (4x CM4 @ 1.5 GHz)](https://www.jeffgeerling.com/blog/2021/turing-pi-2-4-raspberry-pi-nodes-on-mini-itx-board) | Arm | 44.942 Gflops | 24.5W | 1.83 Gflops/W |
 | [Lenovo M710q Tiny (1x i5-7400T @ 2.4 GHz)](https://www.jeffgeerling.com/blog/2023/rock-5-b-not-raspberry-pi-killer-yet) | x86 | 72.472 Gflops | 41W | 1.76 Gflops/W |
+| [Raspberry Pi 400 (BCM2711 @ 1.8 GHz)](https://github.com/geerlingguy/top500-benchmark/issues/49) | Arm | 11.077 Gflops | 6.4W | 1.73 Gflops/W |
 | [Raspberry Pi 4 (BCM2711 @ 1.8 GHz)](https://github.com/geerlingguy/top500-benchmark/issues/13) | Arm | 11.889 Gflops | 7.2W | 1.65 Gflops/W |
 | [Turing Pi 2 (4x CM4 @ 2.0 GHz)](https://www.jeffgeerling.com/blog/2021/turing-pi-2-4-raspberry-pi-nodes-on-mini-itx-board) | Arm | 51.327 Gflops | 33W | 1.54 Gflops/W |
 | [DeskPi Super6c (6x CM4 @ 1.5 GHz)](https://www.jeffgeerling.com/blog/2022/pi-cluster-vs-ampere-altra-max-128-core-arm-cpu) | Arm | 60.293 Gflops | 40W | 1.50 Gflops/W |