I'm breadboarding a new PC build with only MB, CPU, HSF, known good PSU and case speaker.

thebigo

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When I power up, the CPU fan starts up, PSU cycles every 20 seconds or so, and that's it. No beep whatsoever from the case speaker. I've spent many hours reading the posts here on breadboarding. I have never seen a suggestion as to how to definitively determine whether the problem is MB or CPU, at this point. Is that true?

MB - ASRock AB350 Pro4
CPU - Ryzen 5 1600
PSU(s) - OCZ Mod Exreme Pro 600W (used for my previous build, still works)
Thermaltake ToughPower Grand RGB 750W (new, but tested on my previous build)
Case speaker - Kingwin, new, but tested on my previous build
 
Solution
The only way to tell which one (CPU or mobo) is the cause in such scenario, is to test CPU with different mobo. As it is not possible to test any of those components without the other.

thebigo

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I tested with RAM, video card etc I got the exact same results, CPU fan starts up, PSU cycles every 20 seconds or so.

Point being, with just the CPU/HSF installed on the motherboard, powering up is supposed to provide diagnostic beeping indicating no RAM. I get no beeps, which tells me it is the MB or the CPU.

My question is, at this point in the breadboarding process, is there a way to determine which of those is defective?

If the CPU itself is bad or not installed correctly, is the MB supposed to provide diagnostic beeps?
 

thebigo

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It's possible it's a bad case fan header (aka bad MB), but that wouldn't cause the other issues. I would say it's likely that the case fan not working is probably a downstream result of broader issues with the MB.
 

thebigo

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CPU pins are good. Already tested with 2 known to be good PSUs (listed on original post).

I actually just finished RMA'ing the MB, am no longer attempting to rescue this one.

Still my original question goes unanswered. :(
 

thebigo

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