There are a couple reasons. At the time it was released, 4 GB was more RAM than most desktop computer had or would be expected to have in its lifecycle. Also, 32-bit operating system can only access more than 4 GB of RAM if they run in PAE mode. Not all drivers will run correctly with more than 4 GB of RAM, so Windows XP deliberately capped it to avoid problems.
win xp only reconises 4gb in the entire motherboard. i recoment going to windows 2003 as it reconises 4gb in ram and 2 gb in GFX hardware. also win vista is a good OS to run off.
I don't know an answer from my experience, but a friend said he tried to put 4GB on XP professional, and Windows recognized only 3GB. This was the system: Asus P5B motherboard, Kingston value pack 4GB, Intel Core2Duo.
windows ready boost
It depends on the version. 32-bit Windows supports up to 4GB of RAM, whereas 64-bit versions support 4GB + of RAM. It is the same with Windows Vista and 7.
To run windows 7 you need at least 4gb of ram
4gb ram
4GB
Since the only difference in your detail - is the amount of memory (4GB against 2GB) - go for the 4GB machine. The extra memory will help Windows 7 run faster.
The amount of RAM is actually dependent upon the instruction set architecture. For instance: Windows 7 Ultimate, Enterprise, and Professional 32bit can only support 4GB of RAM, while the 64bit version can handle 192GB. Operating System | 32bit | 64bit 7 Ultimate | 4GB | 192GB 7 Enterprise | 4GB | 192GB 7 Professional | 4GB | 192GB 7 Home Premium | 4GB | 16GB 7 Home Basic | 4GB | 8GB 7 Starter | 2GB | N/A Vista Ultimate | 4GB | 128GB Vista Enterprise | 4GB | 128GB Vista Professional | 4GB | 128GB Vista Home Premium | 4GB | 16GB Vista Home Basic | 4GB | 8GB Vista Starter | 1GB | N/A XP | 4GB | 128GB XP Starter Edition | 512GB | N/A Hope this helps :D(my formatting messed up, so that explains why it might be an eyesore)
No, your laptop does not need 4GB of RAM to run Windows 8. The basic specifications for Windows 8 is 2GB for 64-bit or 1 GB for 32-bit. 4GB would help with the processor but would not be necessary.
For WindowsXP, 1GB or more. For Windows Vista and Windows 7, 2GB or more, with 4GB+ being optimal.
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