I have installed Ubuntu 18 recently on my AMD Ryzen 5 2400G CPU. We know that Ubuntu automatically locks and turn off the display after a specific time of inactivity. Once my display goes black like this, I am unable to get it back to the normal state. That is, the monitor remains black irrespective of whatever I do. I tried pressing keys, tapping mouse and even disconnected and reconnected the monitor cable. Nothing happens.
I could listen my CPU is working fine from the sound of fan, that is it didn't go to sleep. Each time this happens, I have to do a hard restart to get things working again. This is really annoying. Is this a known bug? I searched the community but couldn't find anything worth noticing.
For instance, my machine details:
anony@Anony:~$ uname -a Linux Anony 4.15.0-33-generic #36-Ubuntu SMP Wed Aug 15 16:00:05 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux anony@Anony:~$ lsb_release -r Release: 18.04 anony@Anony:~$ lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 8 On-line CPU(s) list: 0-7 Thread(s) per core: 2 Core(s) per socket: 4 Socket(s): 1 NUMA node(s): 1 Vendor ID: AuthenticAMD CPU family: 23 Model: 17 Model name: AMD Ryzen 5 2400G with Radeon Vega Graphics Stepping: 0 CPU MHz: 1578.024 CPU max MHz: 3600.0000 CPU min MHz: 1600.0000 BogoMIPS: 7186.54 Virtualization: AMD-V L1d cache: 32K L1i cache: 64K L2 cache: 512K L3 cache: 4096K NUMA node0 CPU(s): 0-7 Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx hw_pstate sme ssbd ibpb vmmcall fsgsbase bmi1 avx2 smep bmi2 rdseed adx smap clflushopt sha_ni xsaveopt xsavec xgetbv1 xsaves clzero irperf xsaveerptr arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif overflow_recov succor smca