Regards...
Run a program like 3DMark2001SE on the card. See if when
the card is heated up a bit, it fails or misbehaves. It
could be the video card is bad. Enter the video card
manufacturer name and model number on Newegg, then
read the reviews for the product. Sometimes, really bad
video cards fail within the first three weeks of use, due
to bad video card memory, bad GPU, or a badly installed
video card cooler (no thermal compound or not sitting
flush with the chips it is cooling).
Is the fan on the video card spinning ? Is the card
properly seated in the slot ? I like to loosen the
screws on the motherboard, and adjust the position
of the motherboard so that the add-in cards fit without
binding. (Thus, you are adjusting the x-y position of
the motherboard, to align the computer case mechanicals
with the motherboard.) Also note that if you "borrow"
standoffs from one computer case, for use in another,
the offset in the Z axis can cause the add-in cards
to be "tipped". That can result in bad edge card
contact as well.
Paul
It almost sounds like your power supply unit is not up to the task of supplying
the vid card enough power during a cold boot during which the HDDs pull the most
amperage.
Either that or you have a bad or undersized capacitor that lets the voltage dip
momentarily and sets off the beep code.
Buffalo