Upgraded PC won't start.

[Hippolytus]

Ihave upgraded an old PC with new MB Aorus B450 Elite v2, CPU AMD Ryzen 5 4500 and DRAM Corsair Vengeance LPX DDR4 2x 8GB

PSU (not upgraded) WIN Power AD-E500AE A5/A6 (2016). Video Card (not upgraded or installed yet) ASUS GTX750-PH-1GD5-DP.
I have followed suggestions to test all items on a cardboard platform out of the case. I have done this without any success.
When power is turned on, after re-setting CMOS, one led on the board gives a single flash, then all goes dead. Would be grateful for suggestions
as to what else I can do to check assembly. I’m fairly confident of CPU install, it is seated tight and evenly to the socket. Similarly the DRAM.
Although the PSU is probably inadequate if I wanted to game, it has been performing well in its previous setup, and I have refrained from installing the video card until the start/boot problem is solved.

[veeg]

Hello

Give us the complete psu spec’s.

[phillpower2]

PSU (not upgraded) WIN Power AD-E500AE A5/A6 (2016).

You 100% need to get a new PSU before you go any further as the present unit even when out of the box new was complete garbage.

Ihave upgraded an old PC with new MB Aorus B450 Elite v2, CPU AMD Ryzen 5 4500

The MB may need a BIOS update before it can recognise the newer CPU.

I have refrained from installing the video card until the start/boot problem is solved.

The MB may have video ports but they will only work if the CPU has on die video which your Ryzen 5 4500 doesn`t.

You need to get yourself a known good PSU to swap in for testing purposes being an older GPU something Bronze efficiency rated and 400W or above will do.

The RAM speed we will also need to know if the above does not help any.

[Hippolytus]

Thanks for your comments. I followed the advice in previous posts of dismantling everything to do an open test on cardboard.
I was surprised how easy it was to remove the front panel so I could actually trace the front panel wiring to the MB. This revealed a couple of wiring errors, in the front panel section, due to my reliance on a manual for the old MB which was not accurate for my board. When these were corrected the setup started as it should. Phew!! I did not have a monitor connected, so I left Bios and all the rest for another day.
I have noted the comments on the PSU. I did take advantage of the PSU being dismantled to clean it of a mouse nest of accumulated dust. Is a failing PSU likely to cause any collateral damage?

[phillpower2]

Good news and thanks for posting your findings.

I did take advantage of the PSU being dismantled

Please be aware that there are no user replaceable parts in a PSU so a bad one should be disposed of in a responsible manner and any type of conclusive testing will need to be done by a suitably trained Tech who has the required testing equipment and the relevant knowledge as to how to use it, the previous aside the main reason why an end user should never open up a PSU is because even hours after being turned off the inner workings of a PSU can still be holding enough charge to kill a person.

Contrary to common beliefs a CPU is not the most important component of a computer the PSU is, just like the human heart which needs to be strong and free from defects and when one isn’t the consequences can often be terminal.

You are welcome btw

[phillpower2]

Being that the OP revisited the forum but post no follow up the thread shall be marked and closed.