Continuous Beeps

the beep codes vary depending mfg but in short:
IBM: continuous is pwrsupply or mbo failure
all others provide a seq to isolate the problem device

ideally you should hear 1 short beep at sucessful power-on-self-test (post) then no beeps unless there is device failure. It may seem the beeps are continuous even if they really aren't ok.

start first by rmoving all addin cards (just basic hdd, mem, cpu, video) reseat the ram and verify all pwr connections and drive cables are good. If system powers up fine proceed to add cards carefully 1 at a time. if unit still gives trouble you need to take closer look at mem and video first. Be aware that removing and re-installing cards and ram can fracture the mbo.

good luck
rick

See the Tech Republic Support article on BIOS Beep Codes download
https://www.techrepublic.com.com/5100-6255-1043759.html?tag=crm

Under the IBM beep code a continous beep is noted as a motherboard problem and will require replacing the motherboard.

Hi

Reseat your ram and all cards

Continuos beep is usually ram or no monitor found

Keyboard and mouse not connected will show in bios and seldom does any beeps

Ram then video then cards then cpu

fred

Try this.
When your computer fails its POST, the beep codes are often the only clue to determine what's wrong.
https://www.techrepublic.com.com/5129-6249-1549.html

No not the power supply. I believe you bumped the video card taking out the modem. Was the modem close to the video board? I bet it was. Reseat the video board, I would not mess with the memory. This was a result of physical removal of a board in one of the slots. The mem sticks are usually out of touch of those boards and also smaller so not easy to bump and unseat. Also check all cable seating.

All of the above answers are good. I am wondering if you unplugged your power supply before removing are reseating the modem in the pci slot? You should always unplug the P/S before putting in cards on the mainboard. Check all cards and RAM to make sure they are seated well. I think your RAM may not be set good is the main problem.