HELP: ASRock FM2A88M-HD+ Mobo Running RAM in Single Channel Only

[vladman]

Hello,

Wondering if there may be something I could try besides RMAing the CPU.
CPU is AMD A6-7400K.

So, I've upgraded this mobo's BIOS to the latest 2.7 version yesterday, and when I go into the BIOS, it says the RAM is running Single channel only. RAM is Crucial Ballistix Sport 2x8GB kit. BIOS sees all 16GB RAM, even the XMP1 & 2 settings.

I see nowhere in the BIOS to enable dual-channel operation. Thought this was supposed to be automatic when both RAM slots are filled.

The link to the mobo:

http://www.asrock.com/mb/AMD/FM2A88M-HD+/

I emailed ASRock & this was their reply:

"The problem might be the memory controller inside the processor. Inside the processor do have memory control hub.
Please contact AMD for processor exchange."

Of coarse it's never their mobo that is the problem. It's always something else.
Could the A6 CPU really be defective? I have absolutely no other problems with this CPU/PC. Even CPU-Z shows it's running single channel.

Any ideas?

 

[VirtualLarry]

So the board only has two slots, so it's not a problem with slot placement... you filled both of the slots with identical DIMMs, and the OS is reading the entire amount of memory, but CPU-Z and the BIOS are both reading that it is running in single-channel mode?

It sounds like ASRock tech support might be right, you might need to exchange the CPU then.

 

[vladman]

So, I contacted AMD & here is their exact response:

"I conform you that A6-7400K is having only one memeory controller."

Damn, I thought it had dual RAM Channels.

 

[Burpo]

It has 1 memory controller and 2 channels..
Memory controller The number of controllers: 1
Memory channels: 2
Supported memory: DDR3-1866
Maximum memory bandwidth (GB/s): 29.9

http://www.cpu-world.com/CPUs/Bulldozer/AMD-A6-Series A6-7400K.html

 

[PingSpike]

Try running the ram at a lower speed to see if dual channel becomes enabled. This hasn't been a thing for years AFAIK but dual channel in the past sometimes limited ram speed.