CPU LED is red on Sabertooth X79

Hello everyone,

I currently run an i7 4930k and an Asus Sabertooth x79. I bought the mobo refurbished around 3 years ago.

I also have an ‘old’ PC Power & Cooling 950w silver power supply, which I think I’ve had for almost six years now.

Basically, whenever I boot up the PC or wake the PC from sleep, sometimes it powers up with the CPU LED on the motherboard lit with a red color. Causing it to noot boot/start up properly, and have to force restart it.

I can eventually get it booted up, but it takes multiple tries. I’ve even noticed that if I put my GTX 1070 into another PCI-E slot, that causes it to boot up.

Need thoughts on which part of my PC is most likely to be failing. Don’t have other components to test around at the moment, and money is tight.

The PC Power & Cooling 950w is known to have a short service life, that typically gives out by intermittent under-voltage (thus crashes) during use, but if you find your machine waking from sleep on its own, thats normally a good sign its PSU issues. However I’m certainly not saying its your PSU for sure, just if you can find or borrow a PSU that will run your system without paying money for it (eg swap between two machines you own) then it may be a easy thing to rule out.

On the other hand I had this same sort of not wanting to start but did when you moved the graphics card behavior on the i7 970 system I used to have, turned out to be a slowly dying motherboard, but it wasn’t economical to replace in my region so i ended up swapping to a budget newer system of similar performance. However due to how old that system was, this could also be apples to oranges, as it had a separate north and south bridge, while over the years many features got consolidated into the CPU.

Finally try running Memtest overnight. I have no real reason to suspect ram, but its a super easy thing to rule out completely, so why not.

Thanks for the info. It hasn’t been waking from sleep on its own, but everything you had falls in line.

Now that you mention it, I’ve owned this ram for years as well. Wouldn’t surprise me if it’s all starting to go out slowly together. Will try and find another PSU if I can.

Pretty much gonna wait until it no longer powers on though, may be a good time to upgrade to Ryzen and DDR4 at that point.