Problems with Gigabyte GA-EP45-DS3L & TWIN2X4096-6400C4DHX, TWIN2X2048-6400C4DHX

I am building a PC for a friend. Generally, I know you are not supposed to mix sizes of RAM but he went out and purchased the TWIN2X2048-6400C4DHX 2x1GB module because he found a good deal. I recommended the 2x2gb modules, TWIN2X4096-6400C4DHX, and purchased them. He wants to use the PC for video editing so we decided to try to install all the modules for a total of 6GB ram. The CPU is a Q6600.

 

I have a Gigabyte GA-EP45-DS3L motherboard with BIOS revision F9 and I am having problems getting the 2x2gb modules to post at all.

 

Here is list of what I tried.

If I have the 2x1gb modules installed, I can boot into the BIOS no problems and tweak settings. If I install either of the 2x2gb modules it's hit or miss if the BIOS will load. Sometimes the PC will power on, the monitor will never turn on and the PC will shut down and reboot again into an endless loop. Other times it will load but the screen is completely garbled. Intermittently I was able to get the PC to boot having both 1gb modules installed and only one of the 2gb modules installed. After hours of swapping modules trying to see if I could locate a bad module I was able to boot into the BIOS with the full 6gb installed. There I started playing with the settings.

 

The first thing I did was lower the RAM multiplier so the resulting ram speed displays 667 instead of 800. I also relaxed the timings from 4-4-4-12 to 5-5-5-15. I also increased the MCH voltage from 1.1 to 1.3. I am running memtest 2.01 now and it seems to be stable, but I've yet to make it through one pass. However, the system used to completely lock up in under a minute so even a few minutes in MEMTEST seems significant to me.

 

Can anyone please give me ideas on what settings I can try that will be stable? After which, I'm going to attempt to tighten the timings and do some overclocking.

 

Thanks

Yes, once I was able to get the 2x1gb modules to post that was the first thing I did.. sorry forgot to mention that in the original post.

If you populate all four DRAM slots, then you are advised to drop the DRAM bandwidth and raise the memory controller voltage. Mixing and matching versions and capacities is not supported and never assured of stability but you already know this.

 

So, you are advised to drop the bandwidth to 667Mhz.

 

The only memory Corsair supports in a four DRAM slot population is their Quad kits. This does not mean two dual kits or even worse two dual kits of different versions will not work together, just that you have no recourse to RMA Corsair if they do not work together. If there are problems with the DRAM modules, they are still supported via lifetime warranty, but that is for physical defects and errors in a two stick kit mode. Matched Quad sets are highly binned modules for a four slot population. The Dual sets are tested as a kit, not a Quad and warranted as a dual kit, not a Quad setup. You need to Memtest them as Kits (2 modules, not as a four DRAM slot population). If they fail as a kit or singly, then you have RMA. Keep in mind that there is no support for mixing and matching different versions of DRAM either since different version are of different fabrications and/or manufacturers. They might work, they might not work, but you have no support if they do not work. Thus you are advised to buy all the DRAM at the same time and in this way be more assured of getting the same versions. If you buy online, be sure to specify same versions of the modules and do not expect even then that they will work and again, no support unless you purchase a quad kit.

 

For a four DRAM slot population of 800Mhz DRAM you are advised to drop the bandwidth to 667Mhz and raise the NB Voltage +.2v. You can then attempt to recoup some lost bandwidth via the CPU <--> MCH <--> DRAM overclock. Once stability is found, you can then, if you wish, attempt to regain some of the lost bandwidth of the CPU <--> MCH <--> DRAM stream with an overclock. First stability is necessary as some motherboards, even though they state a four slot population, will not work with stability on a four slot population and need to be RMA'd. So, first stabilty, then overclock.

 

Please research this thread:

 

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

 

There is a limitation of the On Motherboard (Intel) memory controller or On CPU (AMD) and a population of all four banks at the full speed of a two bank run. This limitation is across the board with both AMD and Intel chipset based boards, DDR, DDR2 and DDR3.

 

Keep in mind that often issues can arise in the longer term even though you have shorter term stability. The issues seldom damage the DRAM unless you raise the DRAM voltage too high. They damage the on CPU (AMD) 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. This is why you are advised to perform the DRAM lowering and MCH Voltage raising.

Thanks guys for the responses..

 

Since your last post, Ive taken a step back and concentrated on trying to get the PC to run with just the 2x2gb set of RAM, ignoring the 2x1gb set of ram for the time being. With both sticks of 2gb RAM installed, Im only able to get the PC to post about 15% of the time. Isolating to just one stick of memory, I'm able to post 100% of the time with one of the sticks and it's failing when I install the other 2gb module. This would seem to me to be a bad stick of RAM.

 

Also, I pulled some 2x2gb modules out of a working PC of another brand with timings of 5-4-4-5-15 and they work with no problems in the PC, so I believe I've eliminated the motherboard from being the problem.

 

Can you please let me know the procedure for warranty replacement? Can I cross ship the RAM so I can get it sooner?

 

Thanks

whoops, I jsut read the sticky on warranty replacements. Should I create another post in the warranty section or can you provide me a ticket number right here?

whoops, I jsut read the sticky on warranty replacements. Should I create another post in the warranty section or can you provide me a ticket number right here?

 

I'm able to post 100% of the time with one of the sticks and it's failing when I install the other 2gb module. This would seem to me to be a bad stick of RAM.

 

RAM GUY will deal with this on Monday. I'm just a member here.

Have you tried the F10 BIOS? Your board is slightly different from my board, but once I installed the latest BIOS and told it to "accept optimized defaults", all the memory problems went away. I am running the 8500C5 at 1066 and everything is rock solid.

I did flash to F10 bios.. and the problems remained. I'll try the "load optimize defaults" one more time just in case. Incidentally, I am able to get ALL the stick (2x2g plus 2x1gb = total 6gb) working if I use the other brand of RAM from my server plus the corasir 2x1gb modules. I did have to kick back on the multiplier, but it works just fine at 667 mhz..

 

Ramguy, when I fill out the RMA form, it asks for a "TS ticket number" or something like that.. do I need that or can I leave it blank?

 

Thanks again.

Use this form, and it will ask you for a post ID from Ram Guy (386417 for this thread):

 

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