CPU 是否可以支援比英特爾指定更多的記憶體？

Question 1

回答這個首要問題：“英特爾方舟通常是正確的，但並非總是正確。”

任何產品表中的某些規格都可以被視為“通常情況”，而外部因素可能會限製或提高性能。例如，Intel i7-8550U 將其基本時脈速度列為 1.80GHz。但是，可以透過支援硬體超頻來突破這一限制。

為了回答有關 Intel i7-8550U 的具體問題，一些 Intel 第八代 U 系列處理器可能原生支援 64GB 記憶體。

引自[1]，第2.1.1.1節，表2-5：

支援的 DDR4 非 ECC SODIMM 模組配置（H/U 處理器系列）

裸卡版	內存容量	DRAM元件技術	動態隨機存取記憶體組織	DRAM 裝置數量	排名#	行/列位址位的數量	DRAM 內的銀行數量	頁面大小
乙	32GB	16 GB	2048M×8	16	2	17/10	16	8K

透過使用兩個這樣的 32GB DIMM，可以實現 64GB 系統記憶體。

另外，為了在實踐中看到它，以下是您所指的檢測和利用 2x32GB 系統記憶體的確切硬體配置：

環境是前面提到的運行 Debian Linux 的硬體設備之一

root@debian:~# dmidecode -qs system-product-name
FW6E

root@debian:~# uname -a
Linux debian 5.10.0-0.bpo.3-amd64 #1 SMP Debian 5.10.13-1~bpo10+1 (2021-02-11) x86_64 GNU/Linux

CPU是i7-8550U

root@debian:~# dmidecode -qs processor-version
Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz

記憶體為 2x32GB DIMM

root@debian:~# dmidecode
Handle 0x0035, DMI type 16, 23 bytes
Physical Memory Array
        Location: System Board Or Motherboard
        Use: System Memory
        Error Correction Type: None
        Maximum Capacity: 64 GB
        Error Information Handle: Not Provided
        Number Of Devices: 4

Handle 0x0036, DMI type 17, 40 bytes
Memory Device
        Array Handle: 0x0035
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 32 GB
        Form Factor: SODIMM
        Set: None
        Locator: ChannelA-DIMM0
        Bank Locator: BANK 0
        Type: DDR4
        Type Detail: Synchronous Unbuffered (Unregistered)
        Speed: 2667 MT/s
        Manufacturer: Kingston
        Serial Number: C792668A
        Asset Tag: 9876543210
        Part Number: 9905744-067.A00G    
        Rank: 2
        Configured Memory Speed: 2400 MT/s
        Minimum Voltage: 1.2 V
        Maximum Voltage: 1.2 V
        Configured Voltage: 1.2 V

Handle 0x0037, DMI type 17, 40 bytes
Memory Device
        Array Handle: 0x0035
        Error Information Handle: Not Provided
        Total Width: Unknown
        Data Width: Unknown
        Size: No Module Installed
        Form Factor: Unknown
        Set: None
        Locator: ChannelA-DIMM1
        Bank Locator: BANK 1
        Type: Unknown
        Type Detail: None

Handle 0x0038, DMI type 17, 40 bytes
Memory Device
        Array Handle: 0x0035
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 32 GB
        Form Factor: SODIMM
        Set: None
        Locator: ChannelB-DIMM0
        Bank Locator: BANK 2
        Type: DDR4
        Type Detail: Synchronous Unbuffered (Unregistered)
        Speed: 2667 MT/s
        Manufacturer: Kingston
        Serial Number: C2A27761
        Asset Tag: 9876543210
        Part Number: 9905744-031.A00G    
        Rank: 2
        Configured Memory Speed: 2400 MT/s
        Minimum Voltage: 1.2 V
        Maximum Voltage: 1.2 V
        Configured Voltage: 1.2 V

Handle 0x0039, DMI type 17, 40 bytes
Memory Device
        Array Handle: 0x0035
        Error Information Handle: Not Provided
        Total Width: Unknown
        Data Width: Unknown
        Size: No Module Installed
        Form Factor: Unknown
        Set: None
        Locator: ChannelB-DIMM1
        Bank Locator: BANK 3
        Type: Unknown
        Type Detail: None

Handle 0x003A, DMI type 19, 31 bytes
Memory Array Mapped Address
        Starting Address: 0x00000000000
        Ending Address: 0x00FFFFFFFFF
        Range Size: 64 GB
        Physical Array Handle: 0x0035
        Partition Width: 2
[...]
Handle 0x003F, DMI type 20, 35 bytes
Memory Device Mapped Address
        Starting Address: 0x00000000000
        Ending Address: 0x007FFFFFFFF
        Range Size: 32 GB
        Physical Device Handle: 0x0036
        Memory Array Mapped Address Handle: 0x003A
        Partition Row Position: Unknown
        Interleave Position: 1
        Interleaved Data Depth: 2

Handle 0x0040, DMI type 20, 35 bytes
Memory Device Mapped Address
        Starting Address: 0x00800000000
        Ending Address: 0x00FFFFFFFFF
        Range Size: 32 GB
        Physical Device Handle: 0x0038
        Memory Array Mapped Address Handle: 0x003A
        Partition Row Position: Unknown
        Interleave Position: 2
        Interleaved Data Depth: 2
[...]

記憶體由作業系統分配

root@debian:~# free -h
              total        used        free      shared  buff/cache   available
Mem:           62Gi       156Mi        62Gi        24Mi       486Mi        61Gi

memtester 驗證這不是錯誤，確保 61Gi 內存

root@debian:~# memtester 61Gi
memtester version 4.3.0 (64-bit)
Copyright (C) 2001-2012 Charles Cazabon.
Licensed under the GNU General Public License version 2 (only).

pagesize is 4096
pagesizemask is 0xfffffffffffff000
want 62464MB (65498251264 bytes)
got  62464MB (65498251264 bytes), trying mlock ...locked.
Loop 1:
  Stuck Address       : ok         
  Random Value        : ok
  Compare XOR         : ok
  Compare SUB         : ok
  Compare MUL         : ok
  Compare DIV         : ok
  Compare OR          : ok
  Compare AND         : ok
  Sequential Increment: ok
  Solid Bits          : ok         
  Block Sequential    : ok         
  Checkerboard        : ok         
  Bit Spread          : setting 109^C
(Process killed because this would take many hours to fully complete)

[1]：https://www.intel.com/content/www/us/en/products/docs/processors/core/8th-gen-core-family-datasheet-vol-1.html第 8 代和第 9 代英特爾® 酷睿™ 處理器家族和英特爾® 至強® E 處理器家族資料表，第 1 卷（共 2 卷）；修訂版008

免責聲明：我在生產您在問題中提到的其中一台計算機的公司工作。

Answer