You only run one OS at a time (multiboot, so when booting you choose which one to boot). So you can install Ubuntu next to Vista and choose when booting which one to use. This won't influence the speed of Vista in any way.
All you need: enough disc space.
Kees
Hey, I own a HP desktop and was wondering if I should install Ubuntu to either replace Vista or boot along with it. I currently run on a Vista 32-bit OS.
CPU specs: AMD 64X2, 1900 MB currently available (plan on adding 1024 MB of RAM), about 280 GB, 2.6 GHz, NVIDIA GeForce 6150 SE graphics. My only worries are slowing down my comp and compromising it's overall performance. Any input is greatly appreciated!

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