Power On Issue

I have a Dell XPS8700 desktop computer running windows 10 Home. Version 2004; OS Build 10941.1052. It has 3.2- gigahertz Intel Core i5-4460 processor; 999.06 gb hard drive capacity; a DVD=RW GHBON optical drive; memory DIMM1 has 4096 mb installed and DIMM2 has 4096 mb installed as well / 8GB RAM; and a NVIDIA GeForce GT 720 graphics card . 64 GB Operating system, x64 based processor.

I have been having an issue with turning on the computer. It was something that only happened every once in a while at first but recently it started happening more frequently (maybe once a week). Now it is at the point that it takes about 5 minutes of playing with the power on button to get it to turn on. I decided to try replacing the CMOS battery (just sort of hoping that might resolve the issue). That was not the problem and as I have been thinking it might be the power on button itself.

I have looked into getting a replacement power on button assembly for the unit but am also wondering if maybe I should replace the psu as well. The computer was purchased in September of 2014 and I have not done any upgrades or replacements of anything inside the computer - aside from the CMSO battery on the motherboard.

Is replacing the psu something that I should be considering and if so any recommendations on what type of unit I should get to replace it?

I have attached a pic of the psu that is installed in the computer right now.

Thank You

 

I have a spare psu to test any problems. I simply attach the spare out of the case to only the hard drive.
My spare isn't as powerful as the last computer I tested it on but it did verify that the psu was the problem.

Dell uses or at least used to use proprietary psu units so you have to be sure you buy something that is guaranteed to fit in your case.

Unfortunately your picture is too small for me to read much more than Dell and made in China on it.
I did blow it up to 200% and got DP/N 06GXM0 (not sure it is is a zero or an oh as the first and last characters).
DP/N is Dell part number.

Power supply units:
https://www.365powersupply.com/prod...ll-xps-8700-8900-power-supply-psu-hu460am-00/
http://www.parts-dell.cc/product-de...-00-psu-460w-dell-xps-8700-8900-power-supply/

You can do some searching. Make sure that the unit you buy has some sort of warranty.

 

I am so sorry for the delay in replying. I had accidentally turned off the computer and simply could not get it to turn back on. I had already ordered a new power on button (New Power button with Switching Line For DELL XPS 8300 8500 8700 0F7M7N) and once it arrived I figured out how to install it and the computer is working just fine now. I had some doubts that the power button was the issue but since the problem was very intermittent at first and the power on button seemed like one other possibility I thought that I would replace that as well.
It did take a little time to remove the old one since I was being very careful and took pictures of everything I moved each step of the way but it was actually really pretty easy when you come right down to it and that was actually my problem.

This is a larger image of that sticker that is on the psu in the Dell.