2 RAM sets not playing nice together

[FRISH]

So I've been pretty unlucky with ram. In my first build I had to set a stick back, on my next I also had to send a stick back, the replacement was fault and needed sending back, then originally I couldn't find memtest errors on that set but recently tried again and sent them back and got another replacement. I use 2 sets of 2x4GB 1600MHz corsair vengeance, and since getting this last replacement both sets will boot up if I use them on their own, but together it just continues to reboot my PC (mobo shows 03 on the debug led which isn't in my manual, I did wonder if it'd be D3 but then I'd assume it'd be clearer that it was a D).

Using the power of google, I tried upping the voltage to 1.565v which didn't work (now set back down to auto 1.5v), I then tried pressing my cmos button where my PC still reset until I took 1 set out which then let me clear my cmos but after wouldn't let me use them together. I have the latest full release bios, though there are newer ones from 2013 that have increased memory compatibility but are beta drivers. I'm not sure it's wise to use beta bios versions, though if I did I'm not sure how I'd do it since @bios shows the latest stable version and on the mobo site when I extract the exe for the bios it won't run (maybe due to windows 10).

All in all, I underestimated issues in matching RAM sets even though originally they played nice together apart from occasionally BSODs... Also I did test the new replacement with 12 passes of memtest86+ which passed, though my last set seemed to pass too. Using the new set so far to check how it holds up. Anyway, any ideas?

Specs:
OS Windows 10
CPU i5 3570k
Motherboard z77x ud5h
Memory 16GB Corsair Vengeance (4x4GB, 2 sets)
Graphics Card GTX 970 G1
PSU 850W Coolermaster V850

TL;DR: I hate RAM ):

[Biscuit]

Perhaps the issue is the motherboard slot rather than the RAM?

[FRISH]

Perhaps the issue is the motherboard slot rather than the RAM?

Each of the sets work individually in different slots plus before I sent my ram back it did occupy all 4 slots.

[kalniel]

Mem controller on the CPU rather than the RAM.

Make sure *that* is getting enough voltage, and the RAM timings are loose enough for it. Could also be too tight a heatsink fitting on the CPU, or at worse, bent socket pins.

EDIT: Quick google shows O3 error is northbridge/memory controller initialisation error backing up my suspicion.

[FRISH]

So boost cpu vtt? What should I attempt to boost it to?

Edit: Well I increased it up to 1.3v at 0.05 intervals and had no results. Timings were the default 9-9-9-24 since I wasn't sure what if I should change them. Haven't checked the heatsink so far, as for checking the Socket, I'd probably prefer to run 8gb than get some new thermal paste and mess with things there. I've only used pre applied paste so far, so its something I'd avoid doing unless needed. If I can't sort it out it won't be so bad using just 8gb, I thought I'd just see if there was some things to look at.

[FRISH]

use single ram less issue. dual like SLI/Crossfire tend to have more problem.

I might just do that, thanks for the replies.

[FRISH]

Ok so I decided to do 2 things:
1) My graphics card was in the 2nd slot for testing purposes all this time, I decided to put it back in the first slot. While testing my ram before I did notice there was some points where there was turning on and off which I sorted out by ensuring was properly in its place, though it still confused me.
2) I thought I put the sets of RAM in their own channel, so I figured out I'd try mix things up. Turns out they are now in their own channels. It makes sense why I wondered why they were wrong before replacing my RAM when I thought I put them in the right channel... I recalled the slots were 1&3 and 2&4, but those slots were actually next to each other not spaced which is what I got wrong.

I'm not sure which was the problem here, but I'm not entirely sure I want to find out. I still need to see long term stability, but it boots which is more than it used to do. Anyway good news so far