continuous beep on bootup

check if the memory is present. Also check if all the periferals are connected correctly.

A continous BEEP from the time you turn it on?? Replace the keyboard. The beep will appear as soon as the OS starts and the keyboard drivers are loaded. A stuck key or keys will then fill up the keyboard buffer, maybe up to 132 characters and will start a pulsed beep, signifying the buffer overflow. A continous beep from turn on indicates the video memory or system memeory. Be sure the DIMM memory boards are fully seated and tight. Being that you do get video, that may not be at fault but it is possible. Some on board memory maybe designated for the video memory if it's not a plug in card. It is possible that the first 64K of memory is faulted, causing no boot, and a quick check of the BIOS should reveal some clues.

The fact that the system showed the screen logo suggests the beep as warning of HW functioning outside normal range.
Check CPU temperature, CPU fan speed or Power supply voltage.

Press the TAB key while the logo shows. POST text might show the cause. Or enter the BIOS (F1 or F2) and check HW monitor.

Something else to check as well. Many people insist on turning on Alarms in BIOS to warn them of a possible hardware failure which is OK but with a lot of modern M'Boards there are more than one Fan socket present on them and it's possible to enable an Fan Speed Alarm when there is actually no Fan connected so you get a [b]False Reading[/b] and the noise supplied by the alarm indicating a dead fan which will prevent most new systems from booting once a serious error has been detected in the basic BIOS. If you want to check this without opening the case you'll need to look at the System Proprieties in the BIOS and see which Fans are actually running and make sure that say Fan Number 5 which isn't running has not had its alarm turned on. Fan 1 should be the CPU Fan, Fan 2 will be a case Fan if there is one fitted and any others should not be connected unless the system has been altered from original.

Col

Go to HP.com or the BIOS manufacturer and look up the BIOS beep codes for that particular model.

They should have a chart on-line that will tell you exactly what the problem is based on the type of beep.