許容される最大RAMをどのように知ることができますか？

私は古いHP 530ノートブックを発見し、それをSSDと新しいRAMにアップグレードして、弟に学校の課題を完了させる予定です。

システム仕様を理解するためにdmidecodeコマンドを実行し、次のような結果を得ました。

Handle 0x000A, DMI type 16, 15 bytes
Physical Memory Array
    Location: System Board Or Motherboard
    Use: System Memory
    Error Correction Type: None
    Maximum Capacity: 4 GB
    Error Information Handle: No Error
    Number Of Devices: 2

Handle 0x000B, DMI type 17, 27 bytes
Memory Device
    Array Handle: 0x000A
    Error Information Handle: No Error
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 1024 MB
    Form Factor: SODIMM
    Set: None
    Locator: DIMM #1
    Bank Locator: Not Specified
    Type: DDR2
    Type Detail: Synchronous
    Speed: 975 MT/s
    Manufacturer: 7F7FFE0000000000
    Serial Number: 5CB5368D
    Asset Tag: Not Specified
    Part Number: EBE10UE8AFSA-8G-F 

Handle 0x000C, DMI type 17, 27 bytes
Memory Device
    Array Handle: 0x000A
    Error Information Handle: No Error
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 1024 MB
    Form Factor: SODIMM
    Set: None
    Locator: DIMM #2
    Bank Locator: Not Specified
    Type: DDR2
    Type Detail: Synchronous
    Speed: 667 MT/s
    Manufacturer: CE00000000000000
    Serial Number: F405601E
    Asset Tag: Not Specified
    Part Number: M4 70T2953CZ3-CE6 

Handle 0x000D, DMI type 19, 15 bytes
Memory Array Mapped Address
    Starting Address: 0x00000000000
    Ending Address: 0x0007FFFFFFF
    Range Size: 2 GB
    Physical Array Handle: 0x000A
    Partition Width: 2

Handle 0x000E, DMI type 20, 19 bytes
Memory Device Mapped Address
    Starting Address: 0x00000000000
    Ending Address: 0x0003FFFFFFF
    Range Size: 1 GB
    Physical Device Handle: 0x000B
    Memory Array Ma    Handle 0x000A, DMI type 16, 15 bytes
Physical Memory Array
    Location: System Board Or Motherboard
    Use: System Memory
    Error Correction Type: None
    Maximum Capacity: 4 GB
    Error Information Handle: No Error
    Number Of Devices: 2

Handle 0x000B, DMI type 17, 27 bytes
Memory Device
    Array Handle: 0x000A
    Error Information Handle: No Error
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 1024 MB
    Form Factor: SODIMM
    Set: None
    Locator: DIMM #1
    Bank Locator: Not Specified
    Type: DDR2
    Type Detail: Synchronous
    Speed: 975 MT/s
    Manufacturer: 7F7FFE0000000000
    Serial Number: 5CB5368D
    Asset Tag: Not Specified
    Part Number: EBE10UE8AFSA-8G-F 

Handle 0x000C, DMI type 17, 27 bytes
Memory Device
    Array Handle: 0x000A
    Error Information Handle: No Error
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 1024 MB
    Form Factor: SODIMM
    Set: None
    Locator: DIMM #2
    Bank Locator: Not Specified
    Type: DDR2
    Type Detail: Synchronous
    Speed: 667 MT/s
    Manufacturer: CE00000000000000
    Serial Number: F405601E
    Asset Tag: Not Specified
    Part Number: M4 70T2953CZ3-CE6 

Handle 0x000D, DMI type 19, 15 bytes
Memory Array Mapped Address
    Starting Address: 0x00000000000
    Ending Address: 0x0007FFFFFFF
    Range Size: 2 GB
    Physical Array Handle: 0x000A
    Partition Width: 2

Handle 0x000E, DMI type 20, 19 bytes
Memory Device Mapped Address
    Starting Address: 0x00000000000
    Ending Address: 0x0003FFFFFFF
    Range Size: 1 GB
    Physical Device Handle: 0x000B
    Memory Array Mapped Address Handle: 0x000D
    Partition Row Position: 1

Handle 0x000F, DMI type 20, 19 bytes
Memory Device Mapped Address
    Starting Address: 0x00040000000
    Ending Address: 0x0007FFFFFFF
    Range Size: 1 GB
    Physical Device Handle: 0x000C
    Memory Array Mapped Address Handle: 0x000D
    Partition Row Position: 2pped Address Handle: 0x000D
    Partition Row Position: 1

Handle 0x000F, DMI type 20, 19 bytes
Memory Device Mapped Address
    Starting Address: 0x00040000000
    Ending Address: 0x0007FFFFFFF
    Range Size: 1 GB
    Physical Device Handle: 0x000C
    Memory Array Mapped Address Handle: 0x000D
    Partition Row Position: 2

私が知っているのは、RAMメモリの最大容量は4GBですが、4GBスティック1個を購入するのか、2GBスティック2個を購入するのかわかりません。どのタイプのメモリを購入する必要がありますか（DDR2？）？

誰でも私を助けることができますか？

みんなありがとうございます:)