GA-770TA UD3 memory problems, still stumped

[r9ball]

Win 7 Ult 64bit, AMD Phenom II X4 965 Black Edition Deneb 3.4GHz AM3 125W, Corsair H50 cooler, CORSAIR HX Series CMPSU-650HX 650W PS, Crucial 64gb C300 SSD SATA 3, Antec 900 case, BR burner, dvd burner, 2-500gb SATA HD
tried using 2 brands ram, all chips identical within each brand. (the gskill is on their compatibility list)
8gb (4x2gb OCZ AMD Black Edition 240-Pin 8-8-8-24 DDR3 SDRAM DDR3 1600 1.65v (PC3 12800)  OCZ3BE1600C8LV4GK (2-4gb kits)
8gb (2x2gb G.SKILL 4GB (2 x 2GB) 240-Pin 9-9-9-24 DDR3 SDRAM DDR3 1600 1.50v (PC3 12800) l F3-12800CL9D-4GBNQ (2-4gb kits)

Okay a refresh - Got MB back from RMA last week and still has same issue... It will not correctly recognize all 4 ram slots filled with 8gb (4x2gb) ram.
Prior to RMA, tech support via phone tried all the possibilities he could think of and could not get it fixed. They sent it back saying it worked fine with for them using all 4 ram slots,,, I am trying to find out what CPU and the exact ram they tested with (if they answer me). They said they flashed BIOS to F3 (which I had already done and seemed to be fine).
BIOS default has DCTS- unganged,   bank interleave- enabled,    channel interleave-enable.
System works fine with ram in slots 1 and/or 3,, recognized by BIOS and WIN 7 correctly, seems to work fine in those slots even if you change DCTS, bank or channel option.
Will not boot with ram using only slot 2 and/or 4
The problem exists using either brand of ram. Tried at PC 1600 and slower. I change timings and voltage to correct settings. Tried the OCZ at 1.64v and 1.66v since MB does not offer1.65v.

System will not boot with 8gb if DCTs - ganged,, no matter what bank interleave and channel interleave are set on.
System will not boot with 8gb if DCTs - unganged, bank disabled and channel enabled.
System will boot with 8gb if DCTs - unganged, bank and channel both disabled.
System will boot with 8gb if DCTs - unganged, bank enabled and channel disabled.
When it does boot with the 8gb:: BIOS only shows 4gb installed, WIN 7 shows 8gb installed but only 4gb usable, CPU-Z recognizes all 4 ram chips, task manager only reports 4gb.

I am thinling prob with CPU and/or how itand MBhandles dual channels.  Beats me.  Any help/ideas appreciated.
I am only online at night or early morn so be patient if you need any more info,,,,thanks

[Dark Mantis]

Well as you already know you are not alone in this situation. There have been reports of this problem before and as far as I know there has not been a solution found. However we will go through everything and see if we can get somewhere this time. You say the technical support tested it with all slots filled. We need to find out with what ram. My guess would be Kingston as that is their favorite. The PSU I don't think is so important in this case as long as it is a good quality like your Corsair. Give me a chance to think about this and I will post back.

[Dark Mantis]

Did you keep a backup of the tech support's BIOS settings? If so can you check them to see what they were set to?
You are running the latest version of the BIOS, so no options there.
So far I think that you have covered all the things that I can think of to test. We really need to know:

1) What CPU they tested it with
2) What memory they used
3) What settings they got it to work at with all slots filled?
 
See if you can find out these answers and maybe we can get somewhere. Sorry I can't be of more assistance at the moment but some things take time and answers.

[IceColdBeer]

About a year ago, I built a system using a Gigabyte GA-MA770-UD3, using 1 x 4GB-Kit (2xGB) DDR2 Corsair Twin2X DHX CL5 PC6400/800.   No problem.  Then upgrading to 8GB, I accidentally bought the 4GB-Kit DDR2 (2x2GB) Corsair Twin2X CL5 PC6400/800 instead of the 4GB-Kit (2xGB) DDR2 Corsair Twin2X DHX CL5 PC6400/800.

I don't know why, but even though the memory was made by the same manufacturer, had the same speed and latency timing, it still would not work reliably together (even in different combinations in the slots).

So I ended up having to sell the CL5 on ebay and buy some more DHX CL5.    

So, if you can afford too, get some memory that is going to work.  Maybe using http://www.crucial.com to help choose the memory, then if it doesn't work you have good grounds to get your money back

[Dark Mantis]

I totally agree. If you play the game by their rules and something doesn't work you have a comeback.

[absic]

As a matter of interest, will your memory run OK at 1333 Mhz with BIOS set to its default settings?

[Dark Mantis]

As a matter of interest, will your memory run OK at 1333 Mhz with BIOS set to its default settings?

Absic, I take it this is what we were discussing on the other thread about the Phenom II x4, yes ?

[absic]

Yes! Just trying to eliminate things.

[Dark Mantis]

Well I'm glad you spotted it I wouldn't have known. +1 brownie point

[r9ball]

Yes the memory ran at slower speed when tech had me slow it down. That did not cure the problem.
I am beginning to think that it is an incompatibility that exists between this family of AMD CPU channel controllers, and running two banks ram on MB (or at least this brand MB). Hopefully I am wrong.
The default was DCTs - unganged,,,bank interleave-enabled,,,channel interleave-enabled.... Is this normally the correct setting?
Currently I have the GSkill ram installed.
What about the extra timing settings that show up under the 9-9-9-24-2T in the BIOS? I do remember they show 110

[Dark Mantis]

Absic will be on here later to explain the problem and fix in detail to you.

[IceColdBeer]

Absic will be on here later to explain the problem and fix in detail to you.

I'm also waiting to read the solution for this

[r9ball]

Absic would be my hero for a while if a solution exists with this setup.

A few more timings I wrote down,, not sure if they make a difference,,,,using the Gskill  9-9-9-24 2T
TWTR Command Delay  6T
Trfco all 4 dimms at 110ns
write recovery 12T
precharge 6T
row cycle 40T
ras to ras 5T

[Dark Mantis]

Hi r9ball
Sorry that absic hasn't been able to discuss this with you yet but he has arranged with IceColdBeer to lend him his (faulty?)motherboard to do some tesing on and so it makes more sense if he does this first and then hopefully he will have more to tell you. If anyone can sort it out he can. He plans to dedicate a thread to just this project so please keep an eye on the posts.

[absic]

Hi r9ball,

unfortunately there seems to be no quick fix for this memory issue. As Dark Mantis has said, IceColdBeer is also suffering similar problems with this board, he has very generously offered to send me one, so that I can do some testing and see if I can come up with a solution. It could take a week for the board to arrive as IceColdBeer is in Germany and I am in the UK and I can't start testing until I receive it so I'm sorry, it's going to be a little while longer before I have a definite answer. I think you will agree that this is a much better way to try and solve this problem, even though it isn't going to be as quick as you would like.

I do not work for Gigabyte so my tests will be based in the real world, not some lab and I will be using my own components that I know are working OK. However, I have asked Gigabyte (through runn3r) if there are some set standards they use in such tests as I would like to be unbiased and as fair as possible and it will be easier to show any failures with the boards by doing so.

Along with IceColdBeer I will keep you informed of my progress through PM rather than through these threads and once all tests are complete I will start a single thread regarding this issue.

In the meantime, this leaves you with a PC that isn't playing ball and I know how frustrating that can be. I know it isn't the answer but, for the short term, I would suggest that you run your rig with just 4 Gig of RAM installed so that it is stable and have a break from trying to solve this problem. I will be in touch via PM and please feel free to contact me, especially if you think of something that you have tried but not posted about.