When you press the system power button do any of the fans turn on? Have you tried pressing the PSU button and the system power button at the same time, there have been posts stating that the system powered up with those steps. Check all the internal cables and also try reseating the RAM. I have seen RAM that is not fully seated cause a no POST and no fans. The most obvious would be a problem with the case power switch. You can also try disconnecting the power connections from the PSU to everything except the MB. If the system powers up then one of the components is the source of the problem. Connect power one at a time to those components until the no power condition returns.

Thanks for the reply.

When I press the system power button (alienware head) nothing at all happens. Its like you don't even have it plugged into power at all.

Yep I did try pressing both the PSU button and the alienware head power button at the same but no difference. I hear the fans turn on but soon as i let go of the PSU button the fans shut down.

I dont know if I feel comfortable to go inside the PC. I've actually never opened the case up since I bought my Aurora. 

Service Manual. DELL-Chris M>

Today I didn't do anything beside play a few hours of Star Trek Online. The only thing I can think of is could possible updates have caused the problem? I do think Windows did some updates which required a restart and I noticed during the restart my PC turned on and off a few times in a row before it powered back on and through to Windows. I'm feeling that was a BIOS update perhaps now come to think of it? Also Dell Support Center was popping up with some driver updates etc. But all updates were completed in the morning and my PC was still on for at least 4-5 hours and it was working perfectly. Problem happened after I powered it down for about 7 hours and after that it will not turn it back on.

I also have the R8 and since the recent Bios and AWCC updates. I've also begun to experience issues with the system no longer wanting to power on when power button is pressed.

Ohh thats not good to hear

I normally dont do BIOS updates but for some reason Windows Update went and did the update on its own

I just did the update and same thing. Spins up and then nothing.

I have not tried that as of yet. Sorry to hear the CMOS didnt fix it either.

I just reset the cmos, no luck there either.

I beleive a firmware (BIOS) update has been done and it was auto forced through Windows Update which ive never seen happen before.

Shows in the history Firmware 0.1.0.17

So now i can not switch on my Aurora via the button anymore.

At the moment Dell support have told me to dis connect the power cable in the back, hold the power button for 25 seconds and while holding the power button insert the power cable in at the same time. This is the only way i can get the PC to power on at the moment.

They have tried to rollback the BIOS update but so far no luck.

Once i switch my PC off i can no longer turn it back on the tradtional normal way

Try Unplugging the computer, waiting like 10 seconds, and plugging it back in. BIOS updated pretty much did the same thing to my r10. Won't fix your problem, but your pc might at least turn on.