Computer All Of A Sudden Won’t Boot - Red CPU Debug Light ON

The CPU will only be drawing small amounts of power when you first turn on the computer i don't think it would be the PSU holding it back in this case, although you could test the PSU if you know how or get it tested to rule it out but i think at this point i would take heed to the CPU light and replace or try another CPU.

There is Malware out there that can effect the computers firmware so the instance you turn the computer on then that sort of Malware is in effect, it would mean that if this was the case it would be hard to detect unless you have knowledge. Not saying this is the case but its a possibility.

It seems strange that the Computer just stopped working like this unless you have been overclocking and fried the CPU there is no real reason for a CPU to just die they are pretty resilient if you look after them. it could be bad bin but that is a pretty small percent too because of QC measures.

I haven’t done any over clocking of any sort besides maxing out the MHZ in my ram, but this was when I first built my PC over 2 years ago, so I don’t think it’s that. I was using it yesterday then I powered it off and turned it on the next day and it was working like normal 2 days in a row, then today the issue came back so it most definitely could be a CPU issue, although I did take it out to check and it looked fine, no bent pins.

Maybe it was the dried thermal paste that came out of the sides ? because when I replaced my thermal paste, the previous paste was already dry and was flaking on the mobo so it could also be that. Besides that no clue, will probably take it in next week if I don’t manage to fix it as I don’t have any spare parts to test.

Possible candidate if the paste is flaky like that after 2 years then its bad quality paste and a CPU will hit its running temp by the time you are able to interact with the keyboard at boot.

In comparison you only need to reapply paste if you remove the heatsink or if the PC shows signs of cooling degradation so this can mean going indefinitely without new paste depending what ever comes first. So what i mean is 2 years and the paste has done that then its trash paste.

Its ok for it to be dry and hard which is normal but not flaky. 2 days usage with the PC is a good sign if you can cycle the computer 10 or more times in a row then you got a good feeling that was the issue.

browncat2 said:

Greetings All. A few days ago, my PC all of a sudden booted with no display, which was a first, but it booted normally again 10 minutes later.

Sounds like a hardware problem, no I don't have the solution to your problem, but (1) I have a suggestion, and some (2) related stories.

(1) Suggestion, try sleep and wake, so you don't have to turn it on and off every day. If you search the web you will find reasonable explanations why turning on/off your computer induces stress and wear on the electronic components, including some spikes in energy, while sleep and wake works pretty well and reduces such stress, specially on laptops, but you can achieve the same with a desktop computer.

(2) Related cases and stories? my last laptop (Asus - Intel + Nvidia graphic cards) had a similar problem, you could press the on/off button and sometimes would boot up right away, other times it won't. If you gently pressed the button for one sec it would always boot. I couldn't find any solution and I did tried removing and changing stuff. I just kept it always on (sleep/wake), it was what I needed anyway.

Other than that, I've seen the same behavior on other computers, never a "solution" story. Some of these would work as new as long as you removed the battery (on laptops), press on for a sec, reinsert the battery and it would work; desktop computers would behave the same (without battery sure) just by unplugging the power cable. A lot of people end up selling these for cheap.

I just done some testing, took everything out to have a look and found that my PC boots every other day. So one day it will come up with the red CPU debug light, then the very next day after plugging in cables and such, will boot up just fine. Not to sure what’s going on there but as long as it’s posting I guess?. Bit suspect on it just doing that out of nowhere after 2 years of normal gaming, internet surfing and some mild video editing.

I guess as long as it boots i’m fine? might still take it in as there may be a bigger problem i’m not aware of.

Hi, sorry to bring this thread back up but I have the exatly same issue.
Did you manage to solve your problem,if yes how?

Malonexis said:

Hi, sorry to bring this thread back up but I have the exatly same issue.
Did you manage to solve your problem,if yes how?

I had a somewhat comparable issue 1 or 2 years ago. Differences: my system was a lot more ancient than this, good quality parts specially m/b but no debug leds, and besides somewhat intermittent my booting was getting worse until it didn't boot and didn't get video, although the power led and fans did work, and possibly it did the POST last time I don't recall exactly. I replaced the PSU, a good quality one that was in its 13th year, and all fine again.

It had been decades since I last replaced a failing PSU. In that age I used cheap 200/300W ones for computers that didn't way consume as much as current ones (although OP's system is very moderate with a 100W GPU and a 65W CPU, it would be like 210-230W most probably; in this case I prefer lower wattage maybe 400W and higher quality, although last time I searched for something similar I ended up with a 700W one with good brand, lowish price and good expert reviews) and PSU deaths were radical: the computer wouldn't react at all to the power botton, although the latter session and previous ones had been 100% fine. I think I wasn't used to this kind of PSU failing and diagnosed it late.

In this case the PSU is my main suspect.

Last year I also had a motherboard death, but it was different to this. It was w/o previous symptoms during the "landscapes screen" of a bootup to Windows. Everything froze and all subsequent boot attempts resulted in no POST no video, although fans and power LED worked. I tried with as fewer parts as possible (no even drives) with every RAM stick alone (2 total) and in different slots to discard a failing slot too, and I also had spare PSU and gfx card available. Replacing the motherbaord fixed the problem. I used better fans instead (actually among the best "rational" ones) because in the middle I heard the motherbord model had weak VRMs and the processor has 125W TDP. The CPU cooler isn't very effective (I had thought it was better) but I kept it because it blows towards the motherbard and it should help the VRMs.