I'm using Linux as a lightweight OS, just to abuse on my specs. Lubuntu 64bit dual boot for me.
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With Lubuntu I don't use more than 1% of my CPU or RAM most of the time and I use 0% of CPU and RAM even when I'm browsing the Internet because it's using less than one percent of my resources.
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Now imagine the kitchen sink of resources I can throw at emulators with Lubuntu, just about every emulator has a Linux port.
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Here's how to install Lubuntu after Windows 7 and dual boot it. First you install Lubuntu then you do the following:
Choose the install alongside another operating system option when you install Lubuntu and don't use the entire disk or you will overwrite Windows and can't recover it.Download and burn the Windows 7 recovery disc...
http://neosmart.net/blog/2009/window...-repair-discs/
Boot from that disk and choose the command line option.
Type in bootrec.exe /FixMbr then press Enter.
Type in bootrec.exe /FixBoot then press Enter.
Restart the computer.
Once you log on to Windows, download EasyBCD and add an entry for Lubuntu. Select Grub 2 when you create an entry for Lubuntu, then save settings. You can then dual boot both operating systems.