Could be your driver for graphics card. Check that out. Then could be motherboard. Reset motherboard, by removing power from powersupply and push the power on button. If none above works, check your ram.
ROger
I built another pc setup last night and it ran fine. surprise surprise.
running
antec aria case w/ ar300 power supply
2.4 ghz celeron
1 gb pc3200 ddr kingston value ram
dvdrw from sony
gigabyte ga-8lg1000mk board
gigabyte radeon 8x agp card
last night it all ran fine. i did my driver installs, setup some antivirus software and little things. today i burned a dvd and ran update for windows. after it was over i restarted and got repeating beeps..... continuous repeating beeps. i turned it off. rebot did the same thing. reboot again, nothing. i'm lost.

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