2 pairs of TWIN2X4096-6400C5DHX bad idea?

[ogre_x]

Hi,

 

I have a Asus Maximus Formula based rig. CPU is Q9450 and I use 2 pairs of TWIN2X4096-6400C5DHX to achieve 8 Gigs of RAM total. Built the system in late April this year.

 

Standard timings etc.

 

First a pair went bad after a few weeks (secondary bank). Tested out with memtest and found the bad pair and had them replaced from a newer batch. Yesterday the first pair seems to have gone bust (blue screen). Nothing has been done to the rig since i replaced the first pair. It's running 24/7 crunching numbers with BOINC.

 

Tested today with memtest, and sure enough the original pair shows a massive amount of errors in memtest. The replacement pair works alright by itself.

 

So the question is, can something in my configuration cause the memory modules to pop or can it have been a bad batch of sticks I got in the first place?

 

Regards,

 

Fredrik

[DerekT]

It is advised to drop the bandwidth when populating with four DRAM slots. The memory controller can issue errors.

 

Please research this thread:

 

http://www.houseofhelp.com/v3/showthread.php?t=64360&highlight=Unpredictable+results+QUAD2X4096+Gigabyte+X38-DS5

 

The issue is the memory controller and a population of all four banks at the full speed of a two bank run. This issue is across the board with both Nvidia and Intel chipset based boards.

 

Keep in mind that often issues arise in the longer term. The issues seldom damage the DRAM. They damage the on motherboard memory controller which has a harder time keeping up with the demands of a four DRAM slot population being run as fast as a two DRAM slot population. Those who want to be secure in their system either purchase a single kit of the DRAM capacity that the four singles have or they move to a higher bandwidth DRAM and drop the bandwidth. I also advise it as I have personally seen the issues that can and often do arise with a four DRAM slot population running at the full speed of a single kit speed.

 

Also, keep in mind that if you are mixing and matching different fabbed version of the modules and it is never advised nor is it supported to mix and match DRAM versions. This is not to say that the mix/match will not work, just that it is not supported.

 

Download Memtest86+ Version 2.01 from--->

Here

if you are using another version or memtest program. Extract the Memtest86+ Version 2.01 ISO image. Burn the ISO image to an CD-ROM disk.

 

Enter your BIOS and disable the USB Legacy mode as this has been shown to issue non real errors due to a cache of the DOS USB connection. You can enable after the test. Please test the set one apiece in your system. Set one in Slot One (Closest to the CPU) and test. Remove the stick and test the second stick.

 

Results?

[ogre_x]

The results: One stick in the original pair from may is completely broken. Memtest just pours out errors for it. The other stick passed a full test cycle without problems.

 

The exchanged pair worked yesterday for five full cycles in memtest.

 

So I conclude that one stick has broken.

 

When I got the first exchanged pair i Ran all four sticks with memtest for 12 hours without problems before concluding that the configuration seemed stable. The rig has been on 24/7 since.

 

Are you saying that I could permanently damage my MB by trying to run 4 sticks with default timings?

 

I guess my options now are to

 

1) keep the pair that works and exhange the broken pair.

 

2) Try to get corsair to exchange both pairs for an 8 GB matched kit.

 

What are the chances of option 2 happening?

 

Regards,

 

Fredrik

[DerekT]

What are the chances of option 2 happening?

 

I'm just a simple member here but I know of no business that practices such RMA methods. As well, there are NO Quad Kits. I am saying that you can damage your motherboard memory controller if you run all four sticks at the speed of one kit. Just because the DRAM tests out on a long memtest does not take away from the cumulative issues that are longer term and degenerative. You can damage the DRAM and even more likely, the motherboard memory controller will become wonky.

 

Reread that thread I posted.

[ogre_x]

I read the post and I will RMA the module pair that is broken.

 

<rant>

I can use the exchanged pair as a spare, being rather disappointed that the 8Gb jungle seems a bit hairy. I mean reading in one of these forums about the problems with four banks populated makes me wonder why there are four slots on the MB in the first place. The Maximus Formula is by no means a low-end MB.

</rant>

 

Actually Corsair DO have an 8Gb kit, but It wasn't available when I bought my modules:

http://www.corsair.com/_datasheets/Q2X8G6400C4DHX.pdf

 

So If someone wants to go for 8Gb they'd better buy that kit.

[DerekT]

I mean reading in one of these forums about the problems with four banks populated makes me wonder why there are four slots on the MB in the first place.

 

I agree!!!