Core i7 12Gb XMP

[ExMachinery]

Hello everyone!

I'm new here and have some questions!


In my work I'm using virtualization as main tool, so quantity and quality of memory is crucial.
For some time I'm using G.Skill memory sticks for 3 main reasons, good looking, speed, stability.
My 3 intel quads with 8Gb RAM (beautifull blue) just fly and shine!
Now, the reason for posting this.
I'm just surrended to the blazing speed and realibility of Core i7 and the fact I can run with 6 memory slots is awsome.
And I need 12Gb of RAM (GSkill ofc )

So, my i7 system,

Mainboard: Asus P6T Deluxe
Processor: Core i7 920
Memory: 3 sticks of other than GSkill brand (Hey, it was lended by a coworker)


Will I be able to run all 12Gb at 1600MHz with retail timings with 2 of this kit F3-12800CL9T-6GBNQ (beautifull red) flawless?


Will I be able to run XMP with stock i7 speed? (I'm not intented to OC).


Thanks in advance,

A true fan, yours Kat

[G.SKILL]

sorry, but we could only guarantee for 3 sticks in triple channel, not total 6 sticks
and it would be very hot when 6 sticks are all installed
you'll need to add a fan on it
thanks


G.S

[ExMachinery]

Hello,

Well, I got a very good ventilated case and a great cooler (very big, so it will ventilate memory sticks too for sure). Think I'll give it a try anyway. If I succed I'll reply it to you.

Thank you for the answer.

Kat

[Tradesman]

Should work fine, prob want the voltage @1.6, for default timings may have to also kick up the NB and VTT voltage for stability

[G.SKILL]

you could try to keep the settings auto except for DDR3 1600 o see if it could work together
thanks


G.S

[Tradesman]

To clarify, my earlier remark was based on the original P6T Deluxe, (they have a P6T Deluxe ver 2 now out also). It was running the 0306 BIOS, and for 12 GB had to go to 1.6v for stability. With the previous 0202 BIOS we had to tick up the NB and VTT to stabilize. But the 12 GB really flies.....the OS on a Vertex doesn't hurt either.

[GSKILL TECH]

well, i would not recommend to run 6 modules. it is not just the heat issue.
the problem is the memory controller.
tri-channel memory controller has a very weak channel. YEAH, YOU SEE EVERY MOTHERBOARD WANTS YOU TO USE 1-3-5 OR 2-4-6. why? because other channel is WEAK.
if you want to use 6 modules, you might need to

1. increase the QPI volt. (make memory controller stronger)
2. increase the memory volt (make memory signal stronger)
3. decrease the speed of memory. (prevents memory controller overload)

NO3 is the best way to do because 1 and 2 might cause overheat problem

[Tradesman]

Actually on most mobos, say with 4 RAM slots (P43, P45, most chipsets), SLOTS 1 and 2 are physically connected to Channel A, slots 3 and 4 are physically connected to Channel B. Each Channel has 64 bit access, hence when you install in slots 1-3 or 2-4 you are putting a stick in each channel thus enabling DUAL-CHANNEL mode or 128bit access. There is nothing to do with a 'weak' channel.

Also note, I used the 4 slot boards as an example, because the excuse you offer above about tri-channel is the same exact thing you tell people all the time about dual channel have a 'weak' controller.

If what you are saying is true, then what is the 'weak' channel? is it channel A or Channel B, particularly in light of the fact you NEED both channels to run DUAL-Channel and get the 128 bit access

Would appreciate a reply.

[G.SKILL]

Actually on most mobos, say with 4 RAM slots (P43, P45, most chipsets), SLOTS 1 and 2 are physically connected to Channel A, slots 3 and 4 are physically connected to Channel B. Each Channel has 64 bit access, hence when you install in slots 1-3 or 2-4 you are putting a stick in each channel thus enabling DUAL-CHANNEL mode or 128bit access. There is nothing to do with a 'weak' channel.

Also note, I used the 4 slot boards as an example, because the excuse you offer above about tri-channel is the same exact thing you tell people all the time about dual channel have a 'weak' controller.

If what you are saying is true, then what is the 'weak' channel? is it channel A or Channel B, particularly in light of the fact you NEED both channels to run DUAL-Channel and get the 128 bit access

Would appreciate a reply.

it seemed you misunderstand it
the memory controller for dual channel is based on northbridge, while triple channel on X58 is based on CPU
and on X58 platform, normally, we'd recommend users to install memories to slot 2, 4, and 6 since they are stronger than 1, 3, 5
if you have X58 motherboards, you could try to install memory to slot 1, 3, or 5
you'll find some may not even boot, that's why we called the channel weak
that's also why we don't recommend user to install total 6 sticks
thanks


G.S

[Tradesman]

update

I realize that the CPU contains the memory controller, but disagree on your explanation of channels, the architecture is similar to dual channel, except for there are channels A, B, and C, slots 1-3-5 and 2-4-6, essentially the same as dual channel, but with as additional channel, this allows for 192 bit access vs 128 in dual channel. Even at this with today's mobos, it has not reached the limits of the memory controller inside of the i7 series. It is entirely feasible under the specs for the i7, and how it is designed, to run 9 slots instead of the common 6. Unfortunately the X58 chipset is still experiencing growing pains, thus the continued BIOS upgrades by the various manufacturers.

Bellow is possibly a better explanation:

With the coming of Core i7 we've seen the integration on-CPU integrated memory controllers for DDR3 SDRAM with 1 to 3 -- 64-bit memory channels (physically four only three active though). You read it right, a tri-channel memory controller. Therefore total memory bus width goes up from 128 bits to 192 bits allowing a massive bandwidth increase as they ar no longer tied to the FSB.

Intel eliminated those "FSB brakes" by designing Nehalem's architecture to use 64-bit memory controllers which are connected directly with the processor's silicon. As a result this new design should bring a bandwidth utilization of as much as 90%, a nice jump from today's 50-60% utilization for sure. The new controller of course supports both registered (server market) and unregistered (consumer) memory DIMMs. The controller is fast ... very fast, and supports DDR3-800, DDR3-1066, DDR3-1333 JEDEC standards, yet has room for future scalability. The memory controller is able to handle 64GB/s, a full tri-channel DDR3-1333 implementation will only amount to 32GB/s maximum bandwidth utilization.

Do the math and conclude that even DDR3-2000 will not max out the controller.

So then, three memory channels per processor, each channel supports a maximum of 3 DIMMs. Again do the math and a single processor can support a maximum of 9 memory slots. You are of course free to use one or two DIMMS, but for optimal performance, the minimum would however be three, one DIMM per channel. So depending on the motherboard class of use, the board can come configured with three, six or nine memory slots.

[GSKILL TECH]

Actually on most mobos, say with 4 RAM slots (P43, P45, most chipsets), SLOTS 1 and 2 are physically connected to Channel A, slots 3 and 4 are physically connected to Channel B. Each Channel has 64 bit access, hence when you install in slots 1-3 or 2-4 you are putting a stick in each channel thus enabling DUAL-CHANNEL mode or 128bit access. There is nothing to do with a 'weak' channel.

Also note, I used the 4 slot boards as an example, because the excuse you offer above about tri-channel is the same exact thing you tell people all the time about dual channel have a 'weak' controller.

If what you are saying is true, then what is the 'weak' channel? is it channel A or Channel B, particularly in light of the fact you NEED both channels to run DUAL-Channel and get the 128 bit access

Would appreciate a reply.

base on the design of the motherboard. one channel is always weaker than other. especially with DDR3 memory controller. I discuss with many motherboard companies RD, included DFi, Asus, Gigabyte, MSi and EVGA.
memory controller is good enough to handle DDR2 1066. however, some motherboard cannot run DDR2 1066 with 4 sticks and I have it here. you are welcome to our lab and we can show you

[GSKILL TECH]

I realize that the CPU contains the memory controller, but disagree on your explanation of channels, the architecture is similar to dual channel, except for there are channels A, B, and C, slots 1-3-5 and 2-4-6, essentially the same as dual channel, but with as additional channel, this allows for 192 bit access vs 128 in dual channel. Even at this with today's mobos, it has not reached the limits of the memory controller inside of the i7 series. It is entirely feasible under the specs for the i7, and how it is designed, to run 9 slots instead of the common 6. Unfortunately the X58 chipset is still experiencing growing pains, thus the continued BIOS upgrades by the various manufacturers.

Bellow is possibly a better explanation:

With the coming of Core i7 we've seen the integration on-CPU integrated memory controllers for DDR3 SDRAM with 1 to 3 -- 64-bit memory channels (physically four only three active though). You read it right, a tri-channel memory controller. Therefore total memory bus width goes up from 128 bits to 192 bits allowing a massive bandwidth increase as they ar no longer tied to the FSB.

Intel eliminated those "FSB brakes" by designing Nehalem's architecture to use 64-bit memory controllers which are connected directly with the processor's silicon. As a result this new design should bring a bandwidth utilization of as much as 90%, a nice jump from today's 50-60% utilization for sure. The new controller of course supports both registered (server market) and unregistered (consumer) memory DIMMs. The controller is fast ... very fast, and supports DDR3-800, DDR3-1066, DDR3-1333 JEDEC standards, yet has room for future scalability. The memory controller is able to handle 64GB/s, a full tri-channel DDR3-1333 implementation will only amount to 32GB/s maximum bandwidth utilization.

Do the math and conclude that even DDR3-2000 will not max out the controller.

So then, three memory channels per processor, each channel supports a maximum of 3 DIMMs. Again do the math and a single processor can support a maximum of 9 memory slots. You are of course free to use one or two DIMMS, but for optimal performance, the minimum would however be three, one DIMM per channel. So depending on the motherboard class of use, the board can come configured with three, six or nine memory slots.

do you have a X58 motherboard? even for big company like kingston, corsair cannot make DDR3 2000 6 modules to run using their best DDR3 2133 or 2000 CL7, i wonder how you run it at DDR3 2000 6 modules.

[Tradesman]

In my explanation, I used dual channel as an explanation that slot 1 and slot 3 are separate channels (A and B) each is 64 bit, when you fill 1 and 3 you enable both channels - hence dual channel.

Where I added "below is possibly a better explanation" that is an excerp from a white paper on the Core i7 and the capabilities it possesses, it is a theoretical explanation, but counters your continous claims as to weak controllers you've presented to i7 users.

It also gets sort of old when you spout off without reading what people have said, i.e. where did I EVER SAY I ran 12GB of 2000.


As to the X58, it will depend on the mobo, the one where I ran 12GB was at 1600, and it took some time to get stable settings. As you should know the X58/1366 as a mobo is an infant, and with any new chipset/socket combination it will take a while before the boards and their BIOSs are tuned together to reach the full potential. It took mobo makers a long time to get the BIOS on the 680i mobos to a point they could run 1066 RAM. The X58 is no different, it going through growing pains, if you look at the mobos out there, some are getting fairly regular BIOS updates, other makers are slower.
The better boards have reached the point where 12GB of 1600 works without a lot of tweaking, which is something that the RAM manufacturers are watching and testing also - those that are willing to to test more than 2 or 3 DIMMs at a time anyway. i.e. OCZ and Corsair both are already selling 12GB kits. At least 2 that I've seen at 1600.........1800 and 2000 will probably follow soon.
You may have already noticed that majority ofX58 boards currently out there and the newer ones being released claim support for up to 24GB RAM.
What's needed now is for the mobo makers to tweak their boards and for the RAM makers to be testing the boards and putting out RAM that will meet and run under the specs of the chipset.

If your interested in the specs of the X58, they can be found here:

http://www.intel.com/Assets/PDF/datasheet/320838.pdf

[Tradesman]

Based on your comments, checked out at Corsair, one of the first posts I saw was

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We have successfully run 12GB on several different 6-slot MOBOs here in our labs. And, quite a few users of our memory online are posting great results up to about 1600mhz. However, anything past that will be luck of the draw and will be dependent upon your individual memory controller on your CPU. 1866 and especially 2000 are going to be pretty hard to do running 6 up.


Also did a check at OCZ, they also show numerous success stories of 12GB up to 1600/1800 and a few threads on 2000. As I stated earlier, give the mobo makers some time for 1800-2000 and up.

[GSKILL TECH]

yes you can run 6 modules of memory but my point is, if you purchase 2 sets of DDR3 1600 tri-channel, it is almost impossible to get them to run at DDR3 1600. but, if you run it at 1333, it will be ok. we are going to have 6 modules DDR3 1600 soon but each 3 tri-channel you can run it at 1800 speed. basically it is using 2 sets of DDR3 1800 together to run it at DDR3 1600 speed.