No error messages, just sudden restarts? Try opening the case and pointing a fan at the inside, heat build up might be the cause. And eyeball those internal fans while you are there.
I have built a system with a msi k7n2 delta-ilsr with an amd athlon xp 2400 processor. I have a quantum fire ball 30 gig hard drive. When I'm doing work especially when I'm online the computer beeps once and restarts at the same time. About a month ago the power supply burned out and I replaced it thinking that was the problem, but that is not the case. It's back to doing the same thing. Please help!!!!

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