From the information you've given regarding the sound of the fan(s), you're going to have a burnt up computer either power supply or CPU.
Im running on a Vaio, with Pentium 4, 1.8 ghz, 512 DDR ram. I recently upgraded my graphics card to an ATI Radeon 9200 and when i turn it back on i noticed two problems.
1. The screen is shaking much like it would after a Degauss, though its not that violent, just constant slight twitch.
2. The fan is incredibly noisy and spinning at unusal speed.
I was just hoping someone might offer some advice to remedy these probems, much thanks!!

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