Asus Z87 Deluxe Dual Q-Code 51 (Memory Error)

[Legion6789]

I just put together a Haswell system. I picked up an Asus Z87 Deluxe Dual mobo and a 32GB 1866MHz RAM kit. The specific model of the RAM is PVI332G186C0QK.

The problem is I'm getting Q-Code 51 on the mobo LEDs. Unfortunately the mobo manual is a bit vague on what Q-Code 51 specifically means. The manual states:

Q-Codes 50-53: Memory initialization error. Invalid memory type or incompatible memory speed.

I haven't noticed any issues with the system so far. Everything looks ok, the POST shows 32GB and so does Windows. Could this be caused by the fact that it's 1866MHz RAM running at 1600MHz, since I'm not overclocking?

I'm just concerned that it could be a more serious issue like a faulty DIMM that could manifest as corrupted data and/or app crashes down the road.

 

[Legion6789]

So I ran memtest86 on the RAM and it came back with 20 errors on the first pass. I figured the memory must be bad so I exchanged it for a Corsair 32GB set. Again I get Q-Code 51. But now my RAM runs at 1333MHz instead of 1600MHz. Changing the DRAM frequency in the BIOS has no effect.

So I figure it has to be the mobo. So I exchange the mobo and again I get Q-Code 51 and the memory frequency issue. I called Asus and they told me it must be a faulty memory controller on the CPU.

The store where I bought all this stuff is going to love me. First I exchange RAM on the premise that it's defective, but it wasn't. Then I exchange a mobo, again because I believed it was defective, but it wasn't. Now the CPU. I don't know what else it could be, everything has been eliminated.

 

[Legion6789]

Checked the CPU in another mobo. No error. So it looks like the CPU is fine. Also tried GSkill 1600MHz RAM in my system and still got error 51. I'm convinced the bios is just shit and has unreliable error reporting. I don't have any other ideas for what to check, so I'm just going to let it complain about error 51 for the next 5 years or until they fix the bios.

 

[blackened23]

Unless you use the XMP profile, it can do that at times from what I remember. It's really not a big deal though.

Have you tried using it with the XMP profile?

 

[Legion6789]

Yeah, I tried using the XMP profile as well as manual configuration.

 

[saad_ahmed]

Well this problem looks like a Matching problem, you should try another one

 

[powruser]

Let me guess, you're running the 1007 BIOS on your Z87-Deluxe? I had the Z87-Deluxe and everything was fine on the original BIOS w/ 1866mhz Crucial Ballistix Elite memory. Once I flashed to the 1007 BIOS... BOOM, crashed and blue screens left and right. I bought from Microcenter, so I exchanged motherboard for a Maximus VI Hero and the RAM for Corsair Vengeance Pro 2400mhz and everything has been fine since. I've also seen others have issues on Asus' ROG forums w/ the Z87-Deluxe and the 1007 BIOS.

 

[Legion6789]

Let me guess, you're running the 1007 BIOS on your Z87-Deluxe? I had the Z87-Deluxe and everything was fine on the original BIOS w/ 1866mhz Crucial Ballistix Elite memory. Once I flashed to the 1007 BIOS... BOOM, crashed and blue screens left and right. I bought from Microcenter, so I exchanged motherboard for a Maximus VI Hero and the RAM for Corsair Vengeance Pro 2400mhz and everything has been fine since. I've also seen others have issues on Asus' ROG forums w/ the Z87-Deluxe and the 1007 BIOS.

Actually I'm using the Deluxe Dual, not sure if there's any meaningful difference between it and the Deluxe. I'm on BIOS 1008. It came with BIOS 0954.

I just ran Prime95 for 28 hours and no errors or warnings. I haven't had any app crashes or blue screens. I think I'm just going to assume it's a false positive... kinda like my buddy's engine light that's been on for the last 5 years.

 

[Legion6789]

Well this problem looks like a Matching problem, you should try another one

What do you mean by matching problem?

 

[tonight]

I've the same problem with the same motherboard and the Corsair Dominator Platinum kit 16Gb. The memories are 1600 MHz but are set to to 1333 MHz.
Do you have find a solution?

 

[jimrun]

I have the Z87 Expert board / i7-4770K & have the same Q Code 51, with both bios 0903 & bios 1008 ...

I have run with the Redline 977122R at both Auto & XMP; & with the Trident X F3-2400C10D-16GTX at Auto, XMP Profile 1, & XMP Profile 2 ...
... all of the above resulted in the Q Code 51 --- but the rig runs great as far as I can tell so far.

A mod on the ASUS forum has indicated that according to an ASUS contact, this is a Thunderbolt related "test reading" on the Q Code :
... "the POST Code "51" on the Z87-EXPERT is only the test code reporting the success detection of the presence of the onboard Thunderbolt host controller, meaning your system is absolutely fine if you see that code on this board.
That test code will be removed in their next BIOS release."

I guess we'll see with the 12xx bios update ...

 

[tonight]

If it's all ok, why the ram don't set to their original frequency, but a step down?

 

[jimrun]

So, I went into the bios & disabled the Thunderbolt ...
... rig booted & is now showing a Q Code of "A0" ---> that's the number zero, not the letter O ...

Based on that little finding ...
... I would tend to agree that the mod's "ASUS contact's" explanation of what Q Code 51 is indicating is "right on the money", for the ASUS Thunderbolt equipped Z87 boards ...