Dell Inspiron 15 3521 won't start

That sounds like the problem I had. If your laptop is still under warranty, the solution will most likely be to call up Dell Support, send in the laptop and they'll replace the motherboard. That's how they fixed mine. It's been working well ever since. 

I hope that helps. 

Its motherboard problem.. You don't know about it..

I had the same problem with my n5030 and I found out my memory module was bad.

I havIhe same/similar problem with my Inspiron 17r (5721). It started not booting up but emitting a continuous beep sound on an occasional basis. I contacted Dell service, but could not tell them a specific cause. I ran diagnostics which all came up OK. Finally, after the warranty ran out, it got much worse, and now won't boot at all.

Dell service was unresponsive before, and now says 'sorry, out of warranty'.

I've had at least a dozen Dells. The most recent experiences are like this. There's something wrong with Dell quality control.

I would not recommend  a Dell product at present.

I have had dell for yrs and have good luck with them tltis one but I found out my problem.

U just have to be patient and check the memory like I did and see if that works.

But most are throw aways like everything else.

I now have hps too and they have the same problems too.

It may be a mother board problem too if so I would not recommend fixing it unless u really like it.

Good luck.

Hello, I'm receiving a Beep code from my Dell Inspiron 15 3521. I have released the static Power, tried to run hardware diagnostic, and attempted to decipher the beep codes. I get 3 series of 4 beeps, the first of each series being loud and the following 3 being softer. When first pressing the power key, the power and hard drive light illuminate but the hard drive light goes out almost instantly. After the 3rd series of 4 beeps concludes, the power light turns off as well and i then again have a dead machine. This laptop is crucial to my business and I need it up and running to run my day to day business. A speedy response would be greatly appreciated. 

Unplug the system, remove the battery and hold the power button for 30 sec.  Remove the base cover and take out both memory modules.  Reinstall the modules and try again.  If that doesn't solve it, try one module at a time in each socket until you isolate the bad module (replace it) or the bad socket (in which case it's the mainboard that will need replacement).

did everything still nothing happened