1) Becouse files are allways left behind, registries are allways left behinds, and most importantly the dlls that remain active as "common files", even though you unistall the aplications
2) Depends really, on my desktop i have about 14, on my laptop i got 30. Download Process Explorer (free) -
http://www.sysinternals.com/ - to get more information on each process, then google the ".exe" to get even more information. Then download Advanced Startup Manager (trial)
http://www.rayslab.com/startup_manag...p_manager.html - And disable the process you know are safe from startup. Also go to Startup Menu -> Run -> "services.msc" and disable services you don't use
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-------------------------------- Computer Specs ----------------------------------
Intel Pentium IV Prescott 3.0 HT → 4x 512MB DDR-DIMM → ASUS GF 6800 GT
Sound Blaster X-Fi → 2x Maxtor 80 GB (RAID 0)
Hitachi 19'' Monitor → Cambridge Soundworks Desktop Theater
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