Pc rarely boots correctly

[Shady666]

I recently bought New Ram "Kingston HyperX Fury Black DDR3 DIMM PC15000/1866MHz CL10 2x8GB" I bought it because its faster than My older Ram, and ole ones speed was 1600Mhz but I hae only one stick of it and few Times I ran out of memory and My pc crashed. But now when I boot My pc I dont have display nor My keyboards,mouses and headsets light turn on. Weird thing is that sometimes it boots normally, and I want to know why cant it Just always boot normally?

Pc specs:
AMD A10-7800
Asus NVIDIA 960 strix 2gb
Asus A55BM-A/M32BF/DP_MB
Kingston HyperX Fury Black DDR3 DIMM PC15000/1866MHz CL10 2x8GB
Coolermaster g450m
And some 2Tb hdd

Its so stupid that it rarely boots

I have bought this Computer with ole Ram in it and the mb and cpu, but I bought New psu, gpu and Ram to it

Edit: I have read the boot tulee thingy and I have tested booting with one stick only and I have changed sticks places too many times

 

[Starcruiser]

Try testing the memory from Memtest86. That'll usually point out a bad stick of RAM if that is the problem. Also, make sure XMP is enabled in BIOS.
Did you have these problems after changing all those parts? You may need to do a clean install of Windows to get back in working order, Windows doesn't always like multiple hardware changes.

 

[Shady666]

Try testing the memory from Memtest86. That'll usually point out a bad stick of RAM if that is the problem. Also, make sure XMP is enabled in BIOS.
Did you have these problems after changing all those parts? You may need to do a clean install of Windows to get back in working order, Windows doesn't always like multiple hardware changes.

Hello. than you for your help but now I have a new problem, the pc won't boot correctly, its fans are spinning and I can hear everything like the HDD dvd drive spinning and I can see my gpus fans spinning everything is working but I can't do those things that you said because it doesn't boot any more normally. Do I need to buy a new motherboard? I tried to boot with my old RAM and it didn't work. I need help so badly 🙁 I changed my PSU and GPU and everything worked fine it was like half year ago when I changed those.

Edit: Oh sorry, I thought that memtest86 works when pc is on and everything is normal. sorry about that

 

[Starcruiser]

It's certainly starting to sound like a motherboard or a CPU problem all right.
All you can really do is stay swapping parts until it works. The easiest thing to start with is the power supply. Never underestimate how a bad PSU can cause the strangest problems. If that doesn't work, borrow a CPU and swap it in. If that still doesn't work, time for a new motherboard.