• This looks like the sort of problem that might be software, might be hardware might be hard to diagnose. You might like to try raspberrypi.stackexchange.com instead, in case anyone over there has encountered this problem. – David Buck yesterday
• Let me trace back. (1) If Rpi works again after reboot, then it very likely that it freezes and so screen is no longer working and becomes white. (2) If after reboot, Rpi works OK again for another couple of days, then it is likely that it is the “stack overflow” problem. (3) Let me explain what does the “stack” do, and why it might overflow. (4) The stack is a part of the random access memory (RAM) and “process related data” is pushed on to the stack when a program starts running (then called a process). / to continue, … – tlfong01 1 hour ago
• Process related data include starting address of the program, parameters being used etc. When a programs stop running, the process related data is pulled from the memory, freeing space for new comers. (5) Now let me give one of many causes of “stack overflow”: (a) If too many long programs start and ends late, the the stack would use more and more space, and less and less space for new comers. (b) If the house keeper/cleaner is stupid, and does not always notice that some programs have completed and need to pull process related data no longer needed, ie, GARBAGE IS NO COLLECTED, / … – tlfong01 52 mins ago
• Here is a wiki about (5) Stack overflow:en.wikipedia.org/wiki/Stack_overflow. Another related thing is (6) “Memory Leak”: en.wikipedia.org/wiki/Memory_leak. / to continu

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