however from what I read, I would think that a Sempron is not a gamers CPU and you didn't mention the key item, the video card.
I think that buzzing is the CPU and video working overtime.
ok, i just bought a kt600-a mobo and a sempron 2500+ with 512 ddr400 ram. everything works fine execpt when i load up quake 3, the videocard or the motherboard makes a wierd buzzing sound, its not the fan, and the mouse pointer comes thru when im in the game, also the sound ceases. i have a creative geforce 256 ddr agp running windows 98 se.

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