Did you try reseating the RAM? (plenty of YouTubes on how.)
Recently tried to turn on my PC. Was working fine yesterday. Now instead of booting, I get no display plus a Short beep followed by a long beep. The HP help forums says this is a memory problem. My BIOS is AMI.
All fans are working as well.
Specs:
HP Pavilion 6720
AMD Phenom II 840T Quad Core Processor
AMD Radeon 4200
(I don't know what motherboard it is)
Any advice?

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