Alienware x51 does not power on

Did you disconnect/reconnect the power cord into the brick? Then make sure the plug in the system is not being constricted?

Yes. Why does the power button light up but not the side panels? The fans are working too.

But there is no beep and it does not start.

The Power Light on the Alienware X51 is not a diagnostic indicator for a no POST situation. The Power Light has only two states i.e. On or Off. No beeps is actually a good thing. Are you connecting the system to a LCD monitor or TV? Via what port on the system and what cabling?

Its connected to the dell led monitor that came with it, via hdmi. The cables and everything were all from the box.

How do I tell?

Are you using the onboard HDMI port or the mini-HDMI port on the added video card?

Sorry. It's connected to the dell led via dvi

What ever happened with this? I'm having the same issue, only no fan. 

It works just fine, but occasionally when I press the power button, the only thing that happens is the white light on the button lights up. Nothing else. It sits there like a brick. In the past I would unplug it and plug it back in, and press the power button again and it would boot up and work. 

Not this time. It's done. It won't boot up at all anymore. I try holding down the power button until the little white light inside goes off, and then pressing to again, but nothing. unplugging it and plugging it back in doesn't work either. 

I have it plugged in to a 64 inc Visio LED TV via HDMI mini. 

I notice that a USB hub I have connected lights up when I press the power button. It stays lit along with the white light on the power button, but that is it. No other signed of activity. No fan. No beep. absolutely nothing. 

Any help? 

Good god this website is such a mess. How can I open a support ticket? It's a simple thing. You open a support ticket and explain your problem. Someone responds and helps you. Why does this website have to be so utterly confusing and messy? Is that the point? So no one can figure out how to get the support they need? It's working.

It might not be the case, but I had to get my PSU repaired (and tbh at the cost i paid I might as well got it replaced)

Work with support to diagnose the problem 1-800-alienware.  they can arrange if you might need a hardware repair.

I called them and the guy had zero understanding of my issue. I was very articulate and explained it several times to him. He kept thinking my computer was overheating and shutting down. He was unable to understand that the computer won't turn on. It won't boot up. It's like when you try to start a car and it just chugs and never turns over. That's my situation. I know I'm not alone. There are other forum threads with this EXACT issue on the x51. You press the power button, and the white light ON THE POWER BUTTON ITSELF lights up. The indicator light on the USB hub I have plugged in also turns on, but THAT IS IT. No fans. No hard drive. No lights. Nothing. After spending about an hour (not kidding) trying different logical things to get the computer to boot up, it FINALLY randomly worked. Things I did multiple times during that hour:
* unplug all cables connected to the computer including the HDMI and power cable. Wait a minute. Plug the cables back in. Nothing.
* Unplug the power brick from the computer as well as unplugging it from the wall. Waiting for the green light to turn off. Plugging the power brick back into A DIFFERENT OUTLET and then back into the computer. Nothing.
* Removing the mini HDMI cable from the computer and unplugging it from the TV. Connecting a regular HDMI into the full size HDMI port on the PC. Nothing. Tried turning it on with both cables disconnected from the TV, connected to the TV, no cable at all connected to anything, NOTHING
* Setting the system upright (I use it laying on it's side like a PS3) and caressing the case. Talking to it. Pleading with it.
* I did ALL these things multiple times in random order for a little over an hour.
* Just as I was about to give up and make other plans, the computer FINALLY turned on. The last thing I did before it finally booted up was disconnect the power cable from the X51, massage the cord, gently bending it and manipulating it against the natural curves it has adopted, then plugging it back in and pressing the power button. The system instantly came alive. lights on, fans blowing, hard drive spinning. I haven't turned it off since. It's staying on.
* This leads me to believe that MAYBE (probably not) the problem is in the power brick cable. Maybe it's not giving the system the correct amount of power required to fully turn on? Maybe there is a bad connection inside the cable that my massaging temporarily fixed. I don't think this is the case, because as I said above, I manipulated the power brick and cable multiple times while helplessly trying to get the PC to turn on. It didn't work then. I have no idea what the actual issue is. It stinks. I just got this computer on May 03 of THIS YEAR (2012) and it is amazing except for this huge flaw. It has been doing this since May, but I never thought much of it because I was always able to get it to start up on the second try. It's only in the last few weeks that the problem has gotten out of control. Again, since I finally got it to boot up, I plan to just leave it on. It restarts for updates no problem. It runs great and cuts through just about any game I throw at it. No problems at all WHILE IT'S ON AND BEING USED!!! It's just when I shut it down and later on (a few days, maybe a week later depending) go back to boot it up that it becomes a problem. Because it won't start. It won't TURN ON. Hopefully I'll connect with SOMEONE who knows for sure what is causing this at some point. I apparently have 282 days left on my "technical support" warranty. I think I'm also still covered under parts and labor maybe? I don't know. I wish this website wasn't such a mess. Why can't I find chat support or email support? Why do the support people not understand what I am saying to them? 

If it happens again.,.. contact support and If you have issues ask for a supervisor.  You can also provide your service tag to Chris from Dell here on the forums and he can help push if there are any issues.  Together with Chris' help we should be able to get this resolved for you.

Hey! Thank you for helping me out. I hope I don't have to get it sent in for service. I'll feel naked without it. I found Chris up above and am writing him a message. Can't thank you enough for responding.

I just bought an X51.  I appear to have an issue when I plug in my 30 inch dell monitor via dual link DVI.  No boot, period. No fan, nothing. Only a dim power light.  If I use the mini-HDMI (thank god I happen to have one) the machine goes on and boots up.  Also, the integrated graphics HDMI allows the system to boot.  So Dell, why does the machine not boot when using the Dual-Link DVI?

Double posted. Use this thread: http://en.community.dell.com/owners-club/alienware/f/3746/t/19469638.aspx