Only 6GB of Ram "Usable" with 12GB Installed???

[invento123]

So again I've read through some forum posts and cant find any help from them. Recently installed a new CPU cooler and everything was working fine till I noticed only 6 GB of my 12 GB is "usable" by windows. Before I installed the new cooler all 12GB of the ram was uable by windows but again now it shows 12GB of ram but only 5.96GB usable. I dont know what I did, Ive reseated my processor twice and triple checked to make sure there are no bent pins on it. Tested every RAM slot and stick, everything good there. Cleared the Cmos a few times, no change. Booting into the bios shows all 12GB, 2x4GB 667MHz Nanya sticks and 2x2GB 800MHz G.Skill sticks. Only slot 1 and 2 are being "used" by windows, which is 1 G.Skill stick and 1 Nanya stick. Dont know what on earth happened. Any help would be great!

Motherboard: GA-970A-UD3P

Processor: FX-8350 OC to 4.6GHz

 

[LunarDapp]

So again I've read through some forum posts and cant find any help from them. Recently installed a new CPU cooler and everything was working fine till I noticed only 6 GB of my 12 GB is "usable" by windows. Before I installed the new cooler all 12GB of the ram was uable by windows but again now it shows 12GB of ram but only 5.96GB usable. I dont know what I did, Ive reseated my processor twice and triple checked to make sure there are no bent pins on it. Tested every RAM slot and stick, everything good there. Cleared the Cmos a few times, no change. Booting into the bios shows all 12GB, 2x4GB 667MHz Nanya sticks and 2x2GB 800MHz G.Skill sticks. Only slot 1 and 2 are being "used" by windows, which is 1 G.Skill stick and 1 Nanya stick. Dont know what on earth happened. Any help would be great!

Motherboard: GA-970A-UD3P

Processor: FX-8350 OC to 4.6GHz

Sorry you're having issues, hopefully we can get this fixed real quick. So--are you running triple, quad, or dual channel? You need to make sure that the speeds AND the capacity match up in at least each channel. Using different speed RAM can cause instability--and is just all around generally not recommended. If your motherboard is quad channel then you have to run the same capacity RAM at the same speed. No combining 667mhz with 800mhz sticks. I know it worked before, but thats the point behind instability.

 

[invento123]

as far as I know it is running in dual channel

 

[LunarDapp]

as far as I know it is running in dual channel

Make sure that you look at the color-coded RAM lots on your motherboard. Make sure that the g.skills are in one color coded ram slots, and that the nanyas are in the other color code. Also make sure that they are level on the board and fully snapped into the board. You could have mixed sticks of ram in the channels--which is a no no.

 

[invento123]

I've tested every single combination and it seems channel 3 and 4 of the ram slots are dead for some reason. I cant figure out why as I took my CPU out AGAIN and checked every single pin, no problems, no missing pins, no bent pins. I believe the two slots are just damaged as again I can see the memory in them but it wont boot with a stick in either of the two bad slots and windows wont allow me to use the ram in those two slots. RIP my prize jewel