Scroll down to the listing for the various Windows 7 versions as each will be different in how much RAM can be supported. You will need to decide whether you want to go 32 or 64 bit. 32 bit tops out at 4 gbs but, in actuality, will probably use about 3 1/2. RAM doesn't, itself, affect system speed but too little can cause slower performance due to hard drive usage as "virtual memory" when physical memory is used up. The amount of RAM you need depends more on what programs you want to run and how many you want to keep open at the same time. At some point, adding more RAM does nothing for speed. Your process is the major player in that regard.
I am going to buy a new desktop computer. How much ram will Windows 7 use? Also, the way I understand things other programs will be using the ram besides Windows so how much do I need for it to run at it's fastest??

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