Asus P8Z77-I Deluxe (mini-max) rejects 16 GB

[freemarket]

Hi,
Am struggling to get a brand new system:

• http://usa.asus.com/Motherboards/Int...specifications
• Intel Core i7-3770K Ivy Bridge 3.5GHz (3.9GHz Turb...
• CORSAIR XMS3 8GB 240-Pin DDR3 SDRAM DDR3 1333 Desk...

to successfully run Win 7 Ultimate with 16Gb (2x 8Gb sticks).

Both sticks pass Windows memtest and memtest86 both individually and together. Memory error LED on mobo does not stay red when system is running.

Qualified memory support list on the web site is useless as it claims the mobo has
4 DIMM slots while it only has 2 and does not list anything larger than 4Gb. The manual in print and online has a larger list but also does not list any single 8Gb stick:

http://usa.asus.com/Motherboards/Int...7I_DELUXE/#MSL

When both sticks are in, I get general application failures: windows session won't start as winlogonui.exe errors popup and are in the events log.
Otherwise, windows explorer dies and other memory reference errors pop up.

I played it safe and did not get overclocked DIMMs.
ASUS customer support said that this memory was slow for the machine yet still supported this speed (1333) and suggested to set BIOS to the slower DRAM settings.
The Corsair memory was confirmed compatible by corsair support.

Anyone have experience with this mobo/memory combo?

TIA,
Henry

[Delta6326]

You didn't purchase these in a dual channel bundle did you? From the link you have to buy 1x8GB twice, this is why I always suggest you buy all your ram in a bundle like this CORSAIR XMS 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3...... Also this may not be the problem, but I have heard this can happen. I would have gotten 1600 speed as thats the standard speed for Ivy Bridge, like this CORSAIR Vengeance LP 16GB (2 x 8GB) 240-Pin DDR3 S...

Again I'm not saying this is the reason for your problem, but have heard it can happen if you don't buy it in dual channel bundle.

[freemarket]

Originally Posted by Delta6326

You didn't purchase these in a dual channel bundle did you? From the link you have to buy 1x8GB twice, this is why I always suggest you buy all your ram in a bundle like this CORSAIR XMS 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3...... Also this may not be the problem, but I have heard this can happen. I would have gotten 1600 speed as thats the standard speed for Ivy Bridge, like this CORSAIR Vengeance LP 16GB (2 x 8GB) 240-Pin DDR3 S...

Again I'm not saying this is the reason for your problem, but have heard it can happen if you don't buy it in dual channel bundle.

That's a good point and I might have saved a few bucks but no I bought 2 sticks of 8Gb of that type.

I'm looking up data on dual channels and why that is important. The only thing I noticed that was funny was that the second stick caused the memory LED on the mobo to stay red when I snapped it into channel B but seemed to work fine on channel A. The only other difference between the two sticks is that the version on one of them ended in 21 while the version on the other was 20.

So you're saying that a dual channel is made to specifically populate paired memory slots? Does it indicate which one should go into A or B or does this not matter?

Thanks,
Henry

[cadaveca]

Originally Posted by freemarket

So you're saying that a dual channel is made to specifically populate paired memory slots? Does it indicate which one should go into A or B or does this not matter?

That doesn't matter.


What happens is that sticks are tested alone, or in pairs, or triple or quads, etc.


When they are tested, they are binned with specific power draw, etc. A single stick, tested, actually has more leniency in it's binning, since it was tested alone. Two sticks, tested together, get binned within the same guidelines.. except now the CPU is dealing with two sticks.. tolerances must be tighter.

As you increase the number of sticks used, tolerances get tighter.

So, you've got two sticks, binned separately, with loose tolerances, and together they probably exceed what the CPU is ready to deal with = boot issues and stability problems, even though each stick on it's own may test fine.


That said, you'll need to test each stick on it's own, and if they both work by themselves, then yes, the issue is because you bought two separate sticks instead of a kit of two, 99.999% of the time.

This is why, the exact reason why, memory OEMs will recommend buying memory with the number of sticks you intended to run, and not mixing kits.

[freemarket]

Originally Posted by cadaveca

That said, you'll need to test each stick on it's own, and if they both work by themselves, then yes, the issue is because you bought two separate sticks instead of a kit of two, 99.999% of the time.

This is why, the exact reason why, memory OEMs will recommend buying memory with the number of sticks you intended to run, and not mixing kits.

Bingo. Thanks for the explanation.

[cadaveca]

Now, you do have the option of increasing IMC voltage to get then stable, of course, either VCCSA or VTT might help bring stability, but when I've run into this myself, I've never been able to fix it 100%. It doesn't happen often, really, but it does happen.

it can get even worse. Two working dual-stick kits, take one stick out of each to make a new kit...and they might not work together. Mixing kits of any sort can lead to issues like this, single stick, or not.

[freemarket]

Originally Posted by cadaveca

Now, you do have the option of increasing IMC voltage to get then stable, of course, either VCCSA or VTT might help bring stability, but when I've run into this myself, I've never been able to fix it 100%. It doesn't happen often, really, but it does happen.

it can get even worse. Two working dual-stick kits, take one stick out of each to make a new kit...and they might not work together. Mixing kits of any sort can lead to issues like this, single stick, or not.

Nope. It's still brand new. Will get an RMA and swap them both for a kit.

[Delta6326]

Originally Posted by cadaveca

That doesn't matter.


What happens is that sticks are tested alone, or in pairs, or triple or quads, etc.


When they are tested, they are binned with specific power draw, etc. A single stick, tested, actually has more leniency in it's binning, since it was tested alone. Two sticks, tested together, get binned within the same guidelines.. except now the CPU is dealing with two sticks.. tolerances must be tighter.

As you increase the number of sticks used, tolerances get tighter.

So, you've got two sticks, binned separately, with loose tolerances, and together they probably exceed what the CPU is ready to deal with = boot issues and stability problems, even though each stick on it's own may test fine.


That said, you'll need to test each stick on it's own, and if they both work by themselves, then yes, the issue is because you bought two separate sticks instead of a kit of two, 99.999% of the time.

This is why, the exact reason why, memory OEMs will recommend buying memory with the number of sticks you intended to run, and not mixing kits.

Cadaveca say's it in a much more understandable way, than me.

Hopefully they will take the ram back and get you a binned pair.

[freemarket]

Originally Posted by Delta6326

Cadaveca say's it in a much more understandable way, than me.

Hopefully they will take the ram back and get you a binned pair.

I'll update you with results next week after I receive the kit.