Computer not turning on

[Cream Soda]

I'm not sure what's wrong with my laptop, but now it won't turn on. The power button flashes instead of stays on, nothing shows up on the screen, and when you first turn it on it beeps shortly twice, followed by three long beeps. Does anyone know what may be the problem and how I would go about fixing it (or where I could go to get it fixed)

[Mayareira]

First of all, what brand? Those beeps are error codes that differs from one manufacturer to another one. They are generally caused by Hardware Failures like;

Unseated card/adapter
general hardware malfunction
RAM problems(this doesn't really prevent initial booting unless they are completely fried)
Power-related problems
BIOS problems

If your RAMs are user-accessible, you could check and see if they are unseated or something. You should also try to run with battery only, and without battery, directly from power supply.

For the other hardware-related problems you should simply bring it to the service, laptop computers are much harder to work with if you don't have prior experience.

[Cream Soda]

Hp pavillion zd8000 is the brand. I've tried removing and putting back in the ram. I don't have batteries so only from power supply I can power it.

[Olo401]

Hmm going by HP's flash/beep error troubleshooting guide, three beeps is a memory problem... but you said you already tried reseating the RAM. There's also a part there about testing each socket (and/or DIMM if you have more than one) to see if it's a faulty socket or DIMM - if you haven't given that a try yet do so.