Computer Just Stopped Working

So lately, my computer has been running kind of slow and sluggish doing anything really. I scanned it for viruses around a week ago and it found nothing. A few days ago I ran memtest86+ and prime 95 and no errors in either of those. Today, I ran malwarebytes again and it found just some thing in the system restore file, so I removed it, and it wanted a restart so I did, and then nothing happened.

It restarted, and my monitor stayed black(already tested monitor, it works) but it is running, with everything on, fans, lights etc. I built it myself, so I took it all apart and reseated everything, and still nothing. I tried resetting the CMOS, tried 1 stick of ram, no sticks of ram, nothing changes. The motherboard is a 890fxa-gd70, and there is a debug LED panel on it, which says FF, but there is nothing in the manual about that.

Also, the NB phase LED is on, both SB phase LEDs are on, and the 4 CPU phase LEDs are on, but after a little while, it will drop to 1 then go back to 4 after a few seconds. I don't know if that's normal or not, but my guess is either the motherboard or CPU is bad. As for the CPU, it's an AMD Phenom II X6 1100T. Any advice would be helpful.

I'd unplug everything again and just try to turn it on without drives/gpu (if you have an onboard to test) to see if it will post.

Also remove all but 1 stick of ram and alternate ram if it still fails, and if it still does after that, I'd test your PSU first.

edit: what do you mean by "nothing" nothing at all, including no post? or it just won't boot?

Well I tried with 1 stick of ram, and again with no ram, and tried the ram in slot 1 then 4, since a search said to try 1 stick of ram in slot 4. As for nothing, it won't post. Everything is on and running like normal, just nothing happens after that, everything just stays running.

ya you'd have to have the ram in the primary slot, depending on the motherboard, some require a speicic slot to be used if you're only using one stick.

I hate quickboot sometimes, it prevents all of post from working, You'll probably have to check your motherboard;s documentation on how to get post to go manually, if it's not working at all, it could be fried.

I'd check the psu before the motherboard though, do you have a multimeter and a piece of wire to short out the ground and green?

(unplug everything from the computer first).

and ya, I skimmed over that part about the ram the first time, hence why I crossed it out.

Unfortunately I don't have a multimeter, and never tested a PSU before, although I do have wire lol. Guess I'll have to buy one at Walmart.

I've got the same mobo, and have had a similar problem, On the bottom right side of the motherboard there is a power button symbol which is actually a button, press it.

Might wanna check the capacitors on your motherboard if they're not blown up.

If they're like the pic below that could be your issue.

Oddly enough, that worked. I tried it last night while it was running and not doing anything, and held it in for 5 seconds and it turned off, but didn't think to try it to turn it on.


I checked them already, but checked again, and there appears to be no leaking or any bulging on any of them.

One thing I noticed now is that, when I go to the bios, it says I only have 4gb of physical memory, when I have 2 sticks of 4gb. And cpu-z is saying the ram is single channel, but it shows that there is 2 sticks in the SPD tab.

anything appears on your screen when you try to boot?
any odd sounds when booting?

kinda sounds like MOBO needs replacing.

I assume you have checked monitor wiring, and that it is being set on the right channel?

(had a similar issue before where, for some reason, monitor defaulted to VGA port instead of DVI and gave no signal.)

Well it's working now, as in, it posted, and booted windows, and I'm typing this from the computer in question. But no beeps or anything different happens when booting.

And I said above that the first thing I checked was the monitor. I hooked up my ps3 to the monitor and it worked, so I assumed the monitor was fine.

I just don't know why the ram is showing up as single channel, and only half the memory in bios, although cpu-z says the size is 8gb...

I typed all this out, but decided to check one thing in the bios. Wanted to see if the ram was on ganged or unganged mode, but as I hit del to go into the bios, I see on the post screen it says there is 8gb, and sure enough in the bios, it says 8gb of physical memory. I checked anyways, and it was om unganged so I left it alone. And cpu-z says it's in dual channel unganged mode, and task manager/process explorer says 8gb physical memory so I guess it's good now, but not sure why all of a sudden during a reset it decided to change. Guess I'll keep an eye on it for now.