Intel EX58 Missing memory channel

ed2353 · 16 Dec 2011 at 18:12

I have a Gigabyte GA-EX58-UD5 motherboard with triple channel memory and i7-920 CPU.

I increased my DDR3 sticks from 3x2GB to 6x2GB by filling all 6 slots to give 12GB total memory. The sticks are identical Patriot Viper 1600LL series.

However, BIOS only reports 8GB.
By elimination, I know that all the memory sticks are OK and they have been reseated several times now as I moved them around.

By elimination, I found that the sticks in memory channel A (Slots 1 and 2) are the ones not recognised by BIOS.

However, in Windows 7, when I right click on Control Panel, and choose System properties I find "Memory installed 12GB Usable 8GB".
CPU-Z and SANDRA also report memory in every slot.

How do I get memory channel A to be recognised and all 12GB usable?

Thanks

Hyburnate · 16 Dec 2011 at 18:14

Drivers up to date?

Ginger-Menace · 16 Dec 2011 at 18:14

only thing i can think of is to do a cmos reset, jot down your oc settings ( if you have any )

bhavv · 16 Dec 2011 at 18:23

This can happen if the ram is clocked too high, or timings / Dram voltage is too low.

Set your ram to 1333 Mhz 9-9-9-28-2T and 1.65v to diagnose if its the ram or the motherboard.

ed2353 · 16 Dec 2011 at 18:49

Thanks for the fast reponse guys. I'll check your suggestions later this evening.
However, I forgot to add that reverting to using the original 3 slots (6GB) only gave me 4GB recognised (slot 1 missing still). That used to work OK.

A hint elsewhere suggested a CPU seating problem and I had just replaced the air cooler with a water cooler. I didn't remove the CPU, but I'm probably pressing down on it differently, so I'm going to check that out too.

setter · 16 Dec 2011 at 18:51

Yep, ive read on here a few times that a cooler thats screwed down too tight, can affect memory recognition.

Orcvader · 16 Dec 2011 at 21:25

ed2353 said:
A hint elsewhere suggested a CPU seating problem and I had just replaced the air cooler with a water cooler. I didn't remove the CPU, but I'm probably pressing down on it differently, so I'm going to check that out too.

It won't suprise me if this was the problem. Infact I think I can remember a few of these threads cropping up a couple of years back, mostly based on Gigabyte boards. I'm too lazy to check though :rolleyes:

Helios1234 · 19 Dec 2011 at 00:59

ed2353 said:
Thanks for the fast reponse guys. I'll check your suggestions later this evening.
However, I forgot to add that reverting to using the original 3 slots (6GB) only gave me 4GB recognised (slot 1 missing still). That used to work OK.

A hint elsewhere suggested a CPU seating problem and I had just replaced the air cooler with a water cooler. I didn't remove the CPU, but I'm probably pressing down on it differently, so I'm going to check that out too.

Is it an antec unit by any chance? If so, you'll have to loosen the mounting screws slightly. I had that problem with mine.

dmxdex2020 · 19 Dec 2011 at 09:32

Bent motherboard pins? My just did this.