RAM slots being dodgy.

[Kyal]

Basically, for the longest time I was running 4x2 1333mhz DDR3(rando generic from an ACER pc, not sure on brand). Was all working fine etc, a few weeks back I noticed that it was only being recognized as 4gigs, so I checked everything out.

Slot A1 and B1 work fine when used together, slot a2 and b2 work fine together, but when I have 4 sticks in a1&b1 it says theyre empty and a2&b2 are recognized & only 4gigs in windows. CPU-Z recognizes all 4 DIMMs being filled & so does my motherboards map thing of showing what slots on the board are filled(no idea what to call it xD).
I have tested each slot with each stick and they all work fine individually. I do not have another PC to test the RAM/any more RAM to test.
Specs;
i5 3570k
asrock z77 extreme 4
gigabyte 7950
plextor m5s 256gb ssd
500g seagate hdd
asus xonar stx
silverstone strider 750w
corsair 650d.
64bit w7 ultimate
Everything is running at stock.

 

[maniac]

I'm 99% sure you're running a 32-bit operating system, you need a 64-bit one for windows to recognize more than 4gb of ram.

 

[Kyal]

I'm 99% sure you're running a 32-bit operating system, you need a 64-bit one for windows to recognize more than 4gb of ram.

64bit windows.
both ram slots a1&b1 and a2&b2 work fine when just they're being used by them selves, but when I put ram into a2&b2 the other slots disappear from BIOS but still recognized in CPU-z for example.
Also if I use slots a1 & b2/a2&b1, its the same as above, just 2gigs in windows/bios but 4 in cpu-z


assuming motherboard is the problem? anyone have any idea whatsoever lol

 

[Excalabur50]

Try a new bios and see if that helps

 

[Kyal]

Try a new bios and see if that helps

Just reset CMOS, no go. Will try a new BIOS and post results afterwards.

Slipped my mind about the BIOS haha

 

[MicroAlex]

Let us know how it goes, interesting case

 

[SWDescent]

Yeah that's very strange that CPU-Z can still see them but the bios can't, I'd love to hear if you fixed this or not, and then I know if it is the motherboard the first thing they'll ask is if you bent a pin installing the cpu, which if it worked before doesn't seem like the cause.