my solution is : run with voltage 12V + without case. and now the result: [admin@routerboard] > system health pr voltage: 12.3V temperature: 39C [admin@routerboard] > system resource pr uptime: 6h48m40s version: 5.22 free-memory: 245636KiB total-memory: 257108KiB cpu: MIPS 24Kc V7.4 cpu-count: 1 cpu...