Weird problem with Maximus VII Impact (Q-Code 55)

[Amosarthus]

Hi guys, I have a strange problem with my rig (i7 4790K, Maximus VII Impact). Recently I have been unable to boot up my PC due to Q-Code 55, which is a memory problem (I think). So I tried swapping out my 2x8GB Corsair Vengeance Pros for my old but trusty 2x4GB Kingston HyperX Blues. No problems booting there. So, thinking it was a problem with my VPros, I tested them in my old rig (i7 3770, ASUS P8Z77-V) and boots perfectly, nothing wrong. So, I try placing the VPros back into my Maximus build. Nada. Retry using my Kingstons, boots no problemo. Is it a RAM problem or is there something wrong with my Mobo?

 

Maximus Rig:

i7 4790K

ASUS Maximus VII Impact

240GB  Intel 530SSD

3TB WD Black

600W Silverstone SX600-G

Leadtek GTX780

 

Old rig:

i7 3770

ASUS P8Z77-V

1TB WD Blue

750W AcBel PSU

Leadtek GTX780 (I swap the gpu depending on which rig I'm using)

 

Both PCs are running Windows 7 Home Premium 64bit

 

The RAM:

2x4GB Kingston HyperX Blue 1600MHz (works on both rigs single channel, dual channel everything)

2x8GB Corsair Vengeance Pro 1866MHz (only works with old rig, sometimes boots on new rig with single channel on 1st slot tho)

 

Any sort of help would be welcome. I personally think it's a problem with the Mobo RAM slots, but I could be wrong...