Question Stuck at POST

[shipwreck5]

Suddenly, my PC stopped turning on other than for for half a second. I discovered that my old Antec PSU was the problem and replaced it. Now it actually turns on and I can see the POST screen, but thats it. I can't enter the bios or boot menu or anything else. I can only see the POST message which ends with the RAM size and then it just stops there. When I press F8 or any other button it shows that it was pressed but doesn't enter another screen or menu. Any ideas would be greatly appreciated.
Specs:
Xeon x3470
8GB 1333mhz DDR3
Asus p7h55-m pro
Zotac 1050 Ti
And a USB 3.0 card that I tried to remove but still gave the same problem.
Edit: I tried to play around with the RAM sticks and tried to reset CMOS but neither worked.

 

[Aeacus]

Here, next step would be MoBo replacement, or better yet, new CPU-MoBo-RAM combo since yours is quite old.

The thing with PSUs is, that they are the most important component inside your PC because they power everything. Cheaping out on PSU can and most times will cost you more once the PSU goes sky high and takes other components with it. The lower the PSU build quality - the higher the chance of PSU taking other components with it when it blows up. MoBos are especially sensitive to PSU issues and so are GPUs. Basically everything that was connected to PSU can be gone.

Without 2nd PC to test out all your components, i can't tell if only the MoBo is dead. It could be that your CPU and RAM are also gone.

Life lesson: do not cheap out on PSU, ever. Also, do not buy used PSU.
Also, what's the current PSU make and model (or part number)?

 

[shipwreck5]

If the had the cash I would of replaced the cpu and mb but sadly I cant really afford a new ryzen setup. Plus this set up was more than good enough for what I needed. The old power supply was an Antec 350w budget oriented power supply but im not sure about the model number. It's quite surprising that it lasted as long as it did which is 15 ish years granted alot of that time was in storage. I tried 2 new powersupplys one from cougar 500w (CGR BS-500) and cheap one from acetek (p4-450w). I expected that the mb is most likely dead but I hoped somebody had another idea.

 

[Deleted member 14196]

if the old PSU died or was dying, it may have killed off other hardware in the system

 

[cherry blossoms]

Old system, quite possibly damaged by PSU failure.

Few options to try and things to check:
Unplug everything not needed to get to BIOS. Damage/short elsewhere may be causing issues
CMOS battery replaced?
Any beep codes?
Try the Crashfree BIOS Recovery procedure?

 

[Aeacus]

If the had the cash I would of replaced the cpu and mb but sadly I cant really afford a new ryzen setup. Plus this set up was more than good enough for what I needed. The old power supply was an Antec 350w budget oriented power supply but im not sure about the model number. It's quite surprising that it lasted as long as it did which is 15 ish years granted alot of that time was in storage. I tried 2 new powersupplys one from cougar 500w (CGR BS-500) and cheap one from acetek (p4-450w). I expected that the mb is most likely dead but I hoped somebody had another idea.

Your Cougar and Acetek PSUs aren't any better build quality wise as your old Antec unit was. They all are low quality units while there are hints of Acetek PSU being crap quality unit. So, there's that. For good/great quality PSU, look towards any Seasonic unit.

As far as what is exactly dead - that we can't answer until you have 2nd system to test out your CPU, MoBo and RAM. My best guess would be MoBo but given that you get something on your monitor, it also could be RAM. Especially since POST freezes during/after RAM amount detection. So, it could be RAM or it could be memory control chip on MoBo.

 

[shipwreck5]

Tried different ram and also reflashed the bios with an arduino cuz crashfree wasn't working. Still no luck. I guess it's something else with the mb that can't be fixed/replaced.