DDR3 2000 works but DDR3 1600 does not!

qwicker

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Jan 27, 2016
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Hi, I really need some advice here because I am going crazy! I have an older setup (but still good!) running an i7 920 on a Gigabyte EX58-UD3R. The mobo manual says it supports 800/1066/1333/2000+ memory but I don't really expect that to be literal (unless maybe it is which explains my problem).

My setup for the last 6 years has had 2 x 2GB DDR3 2000 G.skill sticks from Newegg (click). I have had them running in dual channel no issues.

I decided I wanted to upgrade my system and run triple channel 12GB (3x 4GB modules). I decided to purchase DDR3 1600 G.skill sticks also from Newegg (click).
(Note, I wound up buying a single stick and set of 2 which gives me 3 identical sticks.

I assumed that the mobo would just downclock the RAM to 1066 as that is what the i7 920 can run at (and I'm not overclocked for the sake of this discussion) and it wouldn't matter that the mobo "doesnt support" 1600.

Now is where things get bizarre. I populated the mobo with 3x 4GB in proper 3 channel configuration (I am 100% positive) and no boot. I systematically remove and swap the sticks around thinking I have a bad one. Well, I find 1 stick that works fine, in any slot. The other 2 sticks will not work even when by themselves. So I assume I am so unlucky that I got not 1 but TWO bad sticks so I get an advanced RMA replacement. So now I have 2 brand new sticks. NEITHER work! What?!?!? How can 1 stick work from the original set but now I have FOUR bad sticks. No I don't buy that at all.

Moving on, I keep the working 4GB stick in DIMM 1 and populate the other DIMMs with my old 2GB DDR3 2000 sticks. Viola, system boots up and says I have 8GB total in triple channel (even though its mismatched.

Therefore, I can conclude that none of the DIMMs are damaged and the DDR3 2000 will work in any slot in any order demonstrating those sticks are definitively good. For good measure I even re-seated the CPU and checked for bent/broken pins of which I found none. The only thing I notice about the new RAM, other than being DDR3 1600 is that they are 1.5V whereas my old ram is 1.65V. I also updated BIOS to the latest version which did not help.

Please help me!
 
Solution
If none work individually, then you prob have the newer with high density chips which aren't compatible. DRAM for X58 is getting hard to find, same with 1156 and the even older 775 mobos that really need low density memory ICs (chips)

qwicker

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Jan 27, 2016
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I've tried each stick individually and only 1 of them works. Absolutely bizarre. And that is 1 of 5 identical sticks that I now have in my home (due to having the advanced RMA set before returning the first set).

Can this be a case of this particular RAM is just not compatible with my motherboard? Though it does not explain why 1 stick works.
 
1st - your motherboard doesn't support tripple channel. If you put in 3 ram sticks, it will operate in single channel mode.
2nd - you said, you're not using overclocking, so motherboard BIOS memory settings are on auto?
In that case your new memory sticks might be missing SPD entries for lower frequencies, that your motherboard can support.
You may need to punch in memory timings and frequencies manually into the BIOS.
 

Tradesman1

Legenda in Aeternum

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The EX58 is a 1366 Tri-channel mobo
 

qwicker

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Jan 27, 2016
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^^right, my mobo supports tri-channel.

Regarding the need to set the timings manually, the board does auto-populate the timings but I have manually set them to match exactly what the specs say. No solution. Also, when only 1 stick is populated, the machine does not POST so I can't do anything
 

Tradesman1

Legenda in Aeternum
If none work individually, then you prob have the newer with high density chips which aren't compatible. DRAM for X58 is getting hard to find, same with 1156 and the even older 775 mobos that really need low density memory ICs (chips)
 
Solution

qwicker

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Jan 27, 2016
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Hmm, I had no idea that DDR3 was not DDR3. I probably have to agree that the memory straight up just isn't compatible, perhaps for the reason you cite. From my troubleshooting perspective I cannot grasp why 1 of the sticks does work thought (I hate when I can't figure something out haha!)

For reference, I'm looking at my old 2GB sticks and they have 16 chips (8 per side). The new 4Gb sticks have only 8 chips on 1 side which means they are 4 times as dense.

Any ideas where I can buy some legacy DDR3 modules? Or is there something I can look for when buying to distinguish?
 

qwicker

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Jan 27, 2016
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So the correct answer did indeed have to do with the density. Thank you so much. I just purchased a 12GB kit (3x 4Gb DDR3 1600) with 8 chips per side (256mb per). This is half the density of the G.skill 4GB sticks I was using. PC booted right up, recognized all the RAM and is even holding my overclock (currently in test process).

Thanks!!