我在 b450m ds3h 主板上运行 ubuntu 20.04。我有 4 个 8GB 内存条，单独测试过它们在同一块主板上都能正常工作。但是，当我将它们全部放入 bios 中时，ubuntus dmidecode 可以看到并列出它们，但是 ubuntu 只使用 16gb。我确实有一张被检测和使用的显卡。我还运行了所有可用的更新以防万一。有什么想法吗？似乎我只需要能够告诉 ubuntu 以某种方式启动并使用它。无论如何，感谢您抽出时间。
dmidecode -t 6 输出：
# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 3.2.1 present.
# SMBIOS implementations newer than version 3.2.0 are not
# fully supported by this version of dmidecode.
dmidecode -t 0 | grep -i 版本
Version: F3
已将 BIOS 更新至版本 F51
lshw -C 内存输出：
*-firmware
description: BIOS
vendor: American Megatrends Inc.
physical id: 0
version: F51
date: 07/29/2020
size: 64KiB
capacity: 16MiB
capabilities: pci upgrade shadowing cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int14serial int17printer acpi usb biosbootspecification uefi
*-memory
description: System Memory
physical id: 9
slot: System board or motherboard
size: 32GiB
*-bank:0
description: DIMM DDR4 Synchronous Unbuffered (Unregistered) 1866 MHz (0.5 ns)
product: CMK16GX4M2B3000C15
vendor: Unknown
physical id: 0
serial: 00000000
slot: DIMM 0
size: 8GiB
width: 64 bits
clock: 1866MHz (0.5ns)
*-bank:1
description: DIMM DDR4 Synchronous Unbuffered (Unregistered) 1866 MHz (0.5 ns)
product: CMK16GX4M2B3000C15
vendor: Unknown
physical id: 1
serial: 00000000
slot: DIMM 1
size: 8GiB
width: 64 bits
clock: 1866MHz (0.5ns)
*-bank:2
description: DIMM DDR4 Synchronous Unbuffered (Unregistered) 1866 MHz (0.5 ns)
product: F4-3200C16-8GVGB
vendor: Unknown
physical id: 2
serial: 00000000
slot: DIMM 0
size: 8GiB
width: 64 bits
clock: 1866MHz (0.5ns)
*-bank:3
description: DIMM DDR4 Synchronous Unbuffered (Unregistered) 1866 MHz (0.5 ns)
product: F4-3200C16-8GVGB
vendor: Unknown
physical id: 3
serial: 00000000
slot: DIMM 1
size: 8GiB
width: 64 bits
clock: 1866MHz (0.5ns)
*-cache:0
description: L1 cache
physical id: b
slot: L1 - Cache
size: 768KiB
capacity: 768KiB
clock: 1GHz (1.0ns)
capabilities: pipeline-burst internal write-back unified
configuration: level=1
*-cache:1
description: L2 cache
physical id: c
slot: L2 - Cache
size: 4MiB
capacity: 4MiB
clock: 1GHz (1.0ns)
capabilities: pipeline-burst internal write-back unified
configuration: level=2
*-cache:2
description: L3 cache
physical id: d
slot: L3 - Cache
size: 16MiB
capacity: 16MiB
clock: 1GHz (1.0ns)
capabilities: pipeline-burst internal write-back unified
configuration: level=3
Memtest报告：
System Information
EFI Specifications 2.70
System
Manufacturer Gigabyte Technology Co., Ltd.
Product Name B450M DS3H
Version Default string
Serial Number Default string
BIOS
Vendor American Megatrends Inc.
Version F51
Release Date 07/29/2020
Baseboard
Manufacturer Gigabyte Technology Co., Ltd.
Product Name B450M DS3H-CF
Version x.x
Serial Number Default string
CPU Type AMD Ryzen 7 2700X Eight-Core
CPU Clock 3731 MHz [Turbo: 3730.7 MHz]
# Logical Processors 16
L1 Cache 16 x 96K (82532 MB/s)
L2 Cache 16 x 512K (64487 MB/s)
L3 Cache 1 x 16384K (20557 MB/s)
Memory 16347M (8553 MB/s)
DIMM Slot #0 8GB DDR4 XMP PC4-23900
Corsair / CMK16GX4M2B3000C15
15-17-17-35 / 2998 MHz / 1.350V
DIMM Slot #1 8GB DDR4 XMP PC4-25600
G Skill Intl / F4-3200C16-8GVGB
16-18-18-38 / 3200 MHz / 1.350V
DIMM Slot #2 8GB DDR4 XMP PC4-23900
Corsair / CMK16GX4M2B3000C15
15-17-17-35 / 2998 MHz / 1.350V
DIMM Slot #3 8GB DDR4 XMP PC4-25600
G Skill Intl / F4-3200C16-8GVGB
16-18-18-38 / 3200 MHz / 1.350V
Result summary
Test Start Time 2020-10-27 01:24:38
Elapsed Time 5:48:06
Memory Range Tested 0x0 - 41F380000 (16883MB)
CPU Selection Mode Parallel (All CPUs)
ECC Polling Enabled
# Tests Passed 48/48 (100%)
Test # Tests Passed Errors
Test 0 [Address test, walking ones, 1 CPU] 4/4 (100%) 0
Test 1 [Address test, own address, 1 CPU] 4/4 (100%) 0
Test 2 [Address test, own address] 4/4 (100%) 0
Test 3 [Moving inversions, ones & zeroes] 4/4 (100%) 0
Test 4 [Moving inversions, 8-bit pattern] 4/4 (100%) 0
Test 5 [Moving inversions, random pattern] 4/4 (100%) 0
Test 6 [Block move, 64-byte blocks] 4/4 (100%) 0
Test 7 [Moving inversions, 32-bit pattern] 4/4 (100%) 0
Test 8 [Random number sequence] 4/4 (100%) 0
Test 9 [Modulo 20, ones & zeros] 4/4 (100%) 0
Test 10 [Bit fade test, 2 patterns, 1 CPU] 4/4 (100%) 0
Test 13 [Hammer test] 4/4 (100%) 0
答案1
技嘉 B450M DS3H（修订版 1.0）
BIOS
您的 BIOS 当前位于 F51。
锐龙
AMD Ryzen 7 2700X 八核
Ryzen 处理器因内存兼容性问题而臭名昭著。当单个 DIMM 工作正常，但满载内存无法工作时，则内存可能不兼容。
转到此CPU 支持列表并确定您的 Ryzen CPU 的型号/系列。
然后转到此内存支持列表并找到适合您的 Ryzen CPU 型号/系列的列表。
确认您安装的内存在列表中。可能不在。您可能需要更换当前的内存。
记忆测试
去https://www.memtest86.com/并免费下载/运行它们memtest来测试你的记忆力。至少完成一次所有 4/4 测试以确认记忆力良好。这可能需要几个小时才能完成。
更新＃1：
输出memtest显示 DIMM 的规格不同，“SPD 延迟”（谷歌搜索）和访问模式似乎不同，速度也不同，影响计算机内存大小。我敢打赌 Corsair 内存在内存列表中，而 G.Skill 不在，对吗？您可能需要退回 G.Skill 内存，然后获取匹配的 Corsair 内存来解决这个问题。