I am going to dual boot my XP with Vista and plan to install 8GB RAM with it. Clearly this will benefit Vista but how will it affect XP x86? My view is that everything over 4GB will be ignored by XP but I can't be sure that it will be unaffected otherwise. Can anyone give me some help on this?
Windows XP and VISTA x32 VS Windows XP and VISTA x64 Most users will be sobered when they equip their systems with 4 GB of RAM and find that only 3 GB is recognized by the BIOS and by Windows. This is neither a bug nor due to any hardware error. The explanation is simple: 32 bit systems can only address up to 4 GB of memory. Additionally, many add-in cards and on-board controllers require memory addresses in order to be accessible. This is called "Memory Mapped IO" (MMIO). Since this memory range has to lie within the 4 GB, it is subtracted from the installed and available RAM. In order to be able to utilize the entire system memory, you will therefore need to use a 64 bit version of Windows XP or Vista. Regardless of which version of Windows you are using, all 32 bit systems are limited to a maximum of 4 GB of RAM. The only exceptions to this rule are the Starter Editions, which are primarily targeted at developing nations. Conclusion: if you often use several memory hungry applications simultaneously, then there's really no way around upgrading your system to 8 GB. Working with applications, and especially switching between them, is much more efficient than with a typical 2 GB configuration. Also, it would even be feasible to run a modern 3D game that already takes up more than 1 GB of memory by itself while having another application with a large memory footprint running in the background. Thus, load times in Windows are a thing of the past, as is the constant swapping of Windows components to the hard drive. The best part is that such an upgrade is not even expensive, as 8 GB of memory is already available for as little as $198. Who don't own a 64 bit version of Windows but have a 32 bit full retail version can order a 64 bit version directly from Microsoft, and will only have to pay shipping and handling fees. Users with an OEM version of Vista aren't quite so lucky. Here, it depends on the goodwill of the PC vendor, as Microsoft does not offer direct upgrade support for such versions. In the worst case, the user will be forced to spend more money to buy another license.