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I think it's one of those things that's super easy when everything goes right and requiring some pretty arcane tricks when they go wrong.

I just recently put together a new PC and I was getting close to done. I plugged everything in before putting the side panels on, hit the power button and...nothing. No fans, no beeps, nada.

Okay, I'll just disconnect the ATX power cable from the motherboard and short PS_ON to ground and see if the PSU fan will spin a bit...nothing again.

Hmm. Maybe the modular cable is bad? Google the pinout for Corsair's "Type 4" PSU to make sure it's what I assume it is, drop my bit of wire down the correct pins directly on the PSU, jam my multimeter probes down a 12v + ground and...hell yeah, getting 11.something volts.

Okay, bad ATX power cable, call Corsair, wait a week, problem solved. My wife was watching me do all this on the breakfast bar and kept asking "how did you know to try that?" and I really didn't have a good answer other than "been doing this or watching my dad do this since I was 8".



I'm not sure I've ever assembled a computer without 1. exhaustively searching the internet about all the components and their interactions, finding no red flags 2. buying and assembling all the components 3. discovering some critical problem that requires some arcane setting to fix that probably downgrades performance 4. searching the internet for this particular problem and getting dozens of hits now that I have a specific symptom to go with my hardware.

Clearly step 1 is going wrong somehow, but, I mean, I'm a fairly typical HN poster, you know, I've got at least intermediate-level search skills, you know?


Certainly there are things that can easily trip up an occasional PC builder.

One of the things I always do these days is look up the memory compatibility for the motherboard I've selected, and then only buy off of that list. There are so many variations in just DDR4 2400 memory, and matching up all the parameters (timing, latency, etc.) is a hassle.


Had my PC for about 15 years built from scratch. Over the years I've gutted and added new parts to the point that I have no original components anymore.

Theres two things I hate dealing with the most when it comes to PC building. Those are (1) building a PC from scratch from all new components (2) debugging a PC when a part died

This is because diagnosing the problem and identifying what was wrong could be so many possible things. Back then as well we also didnt have these nice tools like pcpartpicker.com, all of these great youtube tutorials, just a bunch of forums to debug issues.

PC not turning on? Maybe the power supply is not working. Or maybe its the power button itself is having a problem, the switch might have disconnected. Or maybe the wall power outlet is having issues, and maybe can't handle the load. Maybe you changed out a part recently and didnt connect the pins correctly, or during transportation something disconnected. Have to manually check every wire. Are the fans spinning at least?

Is the OS not booting? Okay, is BIOs at least running? Before that, can you hook up a keyboard into the PC? Is that even registering? Does it need an adapter (older PCs didnt use USB 2.0 ports for keyboard mouse). Do you have compatibility issues with hardware components?

Is the computer registering the RAM? Did you check if you slotted it in correctly, by shoving the pins far enough in and latching it? Its possiblethe RAM you recieved was dead on arrival. Try swapping the outlets and see if anything registers

When you changed the CPU did you make sure you didnt bend any pins? If you did your SOL. Maybe you put too much thermal compound between the fan and CPU.

Between all of these steps, did you make sure to ground yourself and prevent static charge from frying your motherboard?

Is your OS booting but your having software issues? Run safemode and find the culprit.

The list goes on and on and it just never ends. Narrowing down the specific issue was always a PITA.


I remember realizing I could reassemble my dad's 386 out of the parts I had stopped using.

I used to go to a screwdriver shop (in Federal Way?) that had some memory and a power supply sitting around at the counter. They would POST a new CPU and board in front of you before you take them home. Less stress than ordering from some random in the Computer Shopper phonebook.


Ugh, this brings back bad memories. I had a new PC that wouldn't power up, and I couldn't figure out why for 2 or 3 days. Eventually I took the motherboard out of the case and then put it back in. Suddenly everything worked. The best guess I've got is that somehow the motherboard was touching the case in a way that was causing it to short out.


Had the same thing happen to me! Built it on desk, worked, moved to case, didn't work. Rebuilt on desk, worked, moved to case, worked! Whatever, sure.

Had it happen again a couple years later but that time it turns out the motherboard was just DOA. But yeah the time spent confirming that the motherboard was the culprit sucked, and required another PC to swap parts with.


I just built a PC recently and thought the CPU fan header was dead until I got into the BIOS (with no fan spinning) and found that the default fan curve had the fan at -30% from 25C to 75C.


...negative thirty percent?


A mechanism locks up the fan and supplies power to the stalled motor, bringing the CPU up to the desired temperature through resistive heating.




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