Trying to isolate random freezes in Ubuntu 20.04

I'm new to Ubuntu/Linux but an experienced if not expert Windows user. I've set up Ubuntu 20.04 on an older PC with an Asus a8N32-SLI Deluxe (nvidia nforce4 chipset) motherboard and a Radeon HD 7850 as a retro gaming machine for my kids. I have a triple boot with XP, Vista and Ubuntu all loading perfectly. Ubuntu runs fine for a while but crashes periodically with no specific pattern (sometimes while browsing in Chrome or Firefox, typing in search box, starting to install an app, or just idling). I'm using the stock Radeon driver because that's the only thing that supports the old gpu on 20.04. This PC has only 4 GB RAM, but I'm pretty sure it's not running out of memory because it didn't crash when I deliberately loaded the memory running lots of apps, including Chrome and Firefox with multiple tabs, and the swapfile seemed to work fine.

I found some ACPI errors in the logs, e.g.: PI BIOS Error (bug): AE_AML_PACKAGE_LIMIT, Index (0x0FFFFFFFF) is beyond end of object (length 0x5) (20200528/exoparg2-393)

One article suggested disabling APIC in the bios, but I can't or my Windows won't boot, so I disabled APIC by adding "noapic" to the kernel boot options.

I also find the following highlighted in red in kern.log when it froze: \00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00Jul 28 13:31:59 Minas-Morgul kernel: [ 0.000000] Linux version 5.8.0-63-generic (buildd@lgw01-amd64-035) (gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #71~20.04.1-Ubuntu SMP Thu Jul 15 17:46:08 UTC 2021 (Ubuntu 5.8.0-63.71~20.04.1-generic 5.8.18)

Jul 28 13:31:59 Minas-Morgul kernel: [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.8.0-63-generic root=UUID=3de49449-3f64-4c79-9cc0-4d6572ade883 ro quiet splash crashkernel=512M-:192M vt.handoff=7

Can anyone suggest where to look in the logs to identify and fix this issue?

Thanks! Parker

หลังจาก "ปิดระบบอย่างกะทันหัน" หรือที่เรียกว่า "ระบบขัดข้อง" และรีบูต คำสั่งเทอร์มินัล sudo Journalctl -b -1 -e จะแสดงจุดสิ้นสุดของบันทึกการบูตครั้งก่อน หากไม่มีคำแนะนำ ให้สงสัยว่ามีไฟฟ้า/ความร้อนสูงเกินไป

อ่าน ผู้ชายวารสารctl เพื่อดูวิธีดึงข้อมูลจากบันทึก

คุณสามารถค้นหาวิธีที่ฉันใช้ประโยชน์จาก วารสาร ctl ได้ง่ายขึ้นที่ https://askubuntu.com/users/25618/waltinator.