GA-770TA-UD3 and memory instability.

[IceColdBeer]

I have built two PCs of almost the same spec using the GA-770TA-UD3, Athlon X2 and 4GB (2x2GB) Corsair memory DDR3 (TW3X4G1333C9DHX).

Both PCs are having problems with memory stability.

On the first PC, I ran the tests from Memtest.org, the test pass on the first pass, but on the second pass they fail.   

On the second PC, the same problem.    I have already changed the motherboard in the second PC to a different brand and now everything is ok, so before I change the motherboard on the first PC, I'd like to try and find the problem.

In the BIOS the memory is detected as 1066MHz although the memory speed is 1333MHz. The voltage is shown correctly at 1.5V.    Nothing is being overclocked, more like under clocked.   The PSU is a good quality 550W supply, so I don't think power is an issue.

It sounds to be like something is getting hot as the memory initially works in the system and then later fails.    The only thing getting hot inside the PC is the northbridge which runs so hot you can't hold a finger on it.   I've installed a fan but no luck.    The first PC did initially work, but since the hot weather these problems started, or perhaps it's a coincidence.    But the board temp shown in the BIOS is around 40 degrees, so nothing major.

Has anyone else experience problems with memory stability and the GA-770TA-UD3.

Cheers,
-R.

[Dark Mantis]

If the memory failed memtest86 then you have a memory problem. Now youare quite correct in saying that it could be heat related. If the Nothbridge gets too hot to put your finger on I would suspect the figure of 40 degrees as being inaccurate. You said that you tried a fan without any success well it should have helped. Did you remember to use heatsink compound when you fitted it?

[IceColdBeer]

The Northbridge heatsink comes fitted to the board when you buy it.    The CPU has a massive Zalman heatsink which I fitted and I did of course use heat sink compound.

Yes, the motherboard temperature does read a bit low if the northbridge is so hot, but that is the reading from the BIOS.   That isn't something I can control, I didn't design the MB.

Remember I've experienced this problem with two motherboards on the two machines I've built.    

The memory does pass intially, it's only when the machine has been running for a while that it stops working.   The RAM isn't hot, the northbridge is though.

I'll end up having to replace the motherboard again (with a different brand like before) to determine whether it is the memory or not.    

Perhaps a memory issue, I've got some replacement DIMMs coming as I sent the last lot back from the second PC that had this problem.

But it is cheaper to replace the board than the memory.   A lot of hassle, and twice now.

[Dark Mantis]

Itb is quite possibly a motherboard/memory incompatibility. They probably both work fine on their own but just not together. Is the memory on the QVL for this board?

[IceColdBeer]

Maybe the RAM needs more voltage.

I've been advised by tech support to try the following:

"It looks like the SPD ROM of the memory is programmed for DDR3 1066 timings only.
You can set the memory manually to DDR3 1333 timing.
Open bios setup > M.I.T. menu:
Change "Set Memory clock" to "Manual"
Set "Memory Clock" to 6.66

Set System voltage Control to "Normal"

Set "DRAM Voltage Control" to ~1.6V
Most of the DDR3 1333 memory requires a little bit higher DDR3 voltage for stable operation.

Don´t exceed a Voltage above 1.65 V to prevent permanent damage of the memory and the processor´s memory controller.

Now you can check, if the random memory errors are gone."

I'll give this a bash this evening.

[Dark Mantis]

What they told you makes sense because the JEDEK certification states that 1066 is the standard. You can set a memory module up to work at a faster speed than this but it is relaint on the quality of the chips used in manufacture. You have to manually overclock the RAM settings and if you are lucky it will run at a faster speed. The numbers are usually on the side of the modules that they are guarranteed to run at. Often you will need to up the voltage of the memory to get it to run stably.

[IceColdBeer]

I changed the timing to DDR3 1333MHz which is what the RAM is spec'd to operate at.

I did as suggested and tried increasing the voltage from 1.55 V to 1.64 V.

The memory tests from memtest.org showed failures in different locations in pass 1 or pass 2.

It is cheaper to replace the motherboard than to buy new memory that has been tried and tested with the GA-770TA-US3 motherboard by Gigabyte.

I'd be more willing to try different memory if this wasn't the second GA-770TA-UD3 motherboard I've experienced this type of problem with.  

What ever the problem is, I haven't the time to debug this issue.    There are risks in building your own computer system and I've had some bad luck, but at least I learnt a bit along the way.

Any other suggestions are welcome before my new motherboard arrives (different make and newer chipset).    

[Dark Mantis]

Did you check out to see if the memory is on the QVL for that motherboard?

[Dark Mantis]

Well I've just checked the memory specs that you have given against both the Gigabyte and Corsair QVLs and neither one lists it as compatible so I am not surprised that you are having problems.

[IceColdBeer]

If you go to the Corsair website and look for memory that is compatible with the GA770TA-UD3 it lists as follows:

http://www.corsair.com/configurator/product_results.aspx?id=1529994


DDR2-800 (DHX2-6400C5*4GB)
4GB Kit (2 x 2GB)
Latency:  5-5-5-18      Voltage:1.8v            Format:240-pin DIMM

Considering my motherboard is DDR3, why do they recommend DDR2?      DDR2 cannot even be inserted into a DDR3 type motherboard, so if I'd taken the advice from that website I wouldn't have got very far.

According to Gigabyte tech support, the memory I have Corsair memory DDR3 (TW3X4G1333C9DHX) should work.    It is not always easy to buy the memory that is QA'd by Gigabyte as it goes obsolete.

[Dark Mantis]

Doesn't make sense does it? Some error there I guess. Let them know and maybe they agree to change your memory. 

[IceColdBeer]

The memory tests pass (from memtest.org) in the first pass even at the correct voltage.    On the second pass they fail.

Considering I've had this problem on two GA770TA-UD3 motherboards with two different sets of Corsair memory, it starts to point that something is getting too hot on that motherboard.

This goes back to the northbridge heatsink was runs very hot.   

Really Gigabyte should take my motherboard and RAM find out what the problem actually is.   I'm a guinea pig here.

I vote new Motherboard (not a GA770TA-UD3 though).

[Dark Mantis]

The problem being that it's not what we think should happen but what actually will.

Try adding a dedicated fan to cover the northbridge and see if bringing the temperatures down will help with the problem You would only need a small fan, about 80mm would be plenty, and fit it to the heatsink on the northbridge.

[IceColdBeer]

I've already installed a 40mm fan blowing air over the northbridge and there is a massive 120mm exhaust fan sucking air above that.

Perhaps if I tried a different brand of 1.65V memory it would work, but it is still cheaper to replace the motherboard than the memory.

In hind sight I should have gone to http://www.crucial.com and used that website to find the QA'd memory.

About a year ago I built a system using a Gigabyte GA-MA770-UD3 and 2x 4GB-Kit DDR2 Corsair Twin2X CL5, PC6400/800 giving a total of 8GB.    The system is still running fine today.    These were my reasons for choosing Corsair memory again and an AM3 verison of the gigabyte motherboard.

These problems are very time consuming and I really don't have the time.     For me, it is easier just to replace the motherboard as the Gigabyte GA770TA-UD3 and memory are now a write-off.

It is nice to solve a problem, but I just replaced the motherboard (not with a GA770TA-UD3) and memory last time and had a working machine in about an hour.

[Dark Mantis]

It is always worth spending a couple of minutes checking on the memory manufacturer's website to see if the memory is compatible with the motherboard that you have chosen.