[Help!] Screen error and reboots when installing O.S.

[guidosava]

Hi everyone. 5 days ago i was using my pc as usual, when suddenly it turns off. After that, every time i start it, it keeps rebooting before enter windows. I've formatted the hd, but can't install windows again because the pc throws a screen error and reboots everytime the installation begins.
What i did:
1) HDD: Not the problem, i've tried with a new SSD and got the same problem.

2) BIOS: Installed the last BIOS driver and changed the battery

3) Graphic Card: Took it off the pc and started with only the integrated card. Same problem

4) RAM: First problem: If i run memtest86 with the two sticks plugged in, it crashes and reboots. I took off one (the 4gb) and tried with the 8gb and the test runs perfectly.

5) PSU: I've checked with the multimeter without any device plugged, just the psu, and the numbers are right.



Screen error: https://freeimage.host/i/05847a89-8b5c-4b58-8585-09c8016bc31d.JCAUZu



My setup is:



amd fx 6300 3,5 ghz
12 gb ram ddr3 (8gb and 4gb)
amd radeon 7700 1mb 150 mhz
asus m5a78L-M usb3
1tb WD10ezex
PSU 650w sentey black box

Some extra data:
- The temps  are fine according to the BIOS. All coolers are working.

- When i start the pc, i have to wait about 5' to have video signal and power in the mouse/keyboard

- Sometimes the case display works, sometimes does not starts.

- 4 months ago i've changed the CPU's termal paste

I dont know what else to do or check, and since we are in quarantine, i cant take the pc anywhere.
Any advice will be welcome! Ty all!

[patio]

One of those RAM stiks is the issue...try the clean install with the one that passed...

[guidosava]

I've tried with the two sticks separately in every one of the 4 slots, and every time i got the same problem.

Recently i've started the pc without the external graphic card (only with the integrated) + one ram stick (4gb) and tested the 12v line with the multimeter from the start untill it crashes and reboots. Starts at 11,30v and crashes with 11,70v...

By these numbers i guess the problem is not the PSU, right?

Could be the ram slots? How can i check the motherboard?

[patio]

Whenever testing with only 1 stik of RAM it goes in the slot closest to the CPU...
Thats a garbage PSU BTW if it came with that case.

[guidosava]

I took this photo of the PSU (can't open it because the screws are bad, tomorrow i will try again)
Does it look bad?

https://freeimage.host/i/psu.JCYGS4

[Lisa_maree]

It's the power supply. The 12volts should be constant if it is changing and going as low as 11.3v then the power supply needs to be replaced. Get a good quality supply even in the lock down you should be able to get one couriered to you.

Something like this one if it is available in your country   Silverstone TUF Gaming ET550-HG 550W Modular ATX 80plus Gold PSU

In the photo you just posted the white glue is there to hold the components (capacitors) during manufacture it is not a failing component. Those parts look to be in the power supply output circuit and confirms Patio's statement "Thats a garbage PSU BTW if it came with that case."

[guidosava]

I see... Well, i will search what options i have available here and see what is the best for my pc. Ty a lot!

[guidosava]

Today i checked these numbers in te BIOS and they look pretty good to me (still have the same restart problem). If the PSU is the problem, why these numbers are correct?

https://freeimage.host/i/2dcdf603-5846-4b43-a751-797218792830.JCsifS

Ty all!

[patio]

Because there is little or no system load when you are in the BIOS...thats why.

[Lisa_maree]

Hi
The numbers are not correct. 5.19v reading on the 5 v rail is on the verge of being out of tolerance which is a maximum of 5.2 v and a minimum of 4.8 v.

I would believe your multi meter over the motherboard voltage sensors. Also a switch mode power supply should be sensing the output voltages and compensating for differing loads. Your power supply isn't doing this and is likely if it fails to go over voltage causing substantial damage. You should replace it if only for this reason.