Pavilion Media Center m8100n won't start up

my hp pavilion m8100n acts like it wants to start up, but there is no display on the monitor. my machine makes one short beep, followed by a pause, then one long beep; however, a short beep followed by a long beep is not on the "meaning of beeps in recent award bios systems" chart.



After owning what was in 2007 an $800+ desktop for less than five years, this m8100n will not start up. Months of blue screen crashes (about once per 3-4 days) and freezes have now transpired into a machine that will not start up. The monitor is black, the monitor's power button is orange instead of blue, even though power is on and computer is running.



It makes one short beep sound, followed by a long beep sound. After a few seconds, it repeats the beep sounds.



This has Windows Vista, version 2.



Most recently, I has out of town for a few days, so I unplugged it. When I returned, the above-mentioned problem occurred and is ongoing. ... I was out of town for two weeks in December, but left it plugged in, but when I returned I had multiple blue-screen crash problems that I hadn't had previously. So, apparently, you can't leave this product unused for a lengthy period of time. These are some of the messages I have received during crashes:



Bad pool header BOOTMGR image is corrupt



PFN_LIST_CORRUPT REFERENCE_BY_POINTER



Driver IRQL Not less or equal



....



As a novice, I have no idea what these messages mean and HP is no help, whatsoever, after the first year. My HP laptop, which cost around $600 in 2007, also does not work. So, why continue buying HPs?