02-18-2012 09:39 AM
In readyness of Ivy Bridge I've bought 16Gbyte of Ballistix Tactical CL9 DDR3. I'm not into overclocking just want my system to run stable and the maximum speeds it is rated to support.
Usually I buy bog standard Crucial memory, always been flawless in the past, however as Ivy Bridge will support DDR3-1600, and the standard Crucial memory is rated at CL11, I bought Ballistix Tactical rated to 1866 with CL9 timings.
While I'm wating for Ivy Bridge I've installed the memory into my current system, which only goes upto 1333, but surprised to see that the SPD only shows official JEDEC ratings up to DDR3-1333, why no support for 1600 considering this memory is rated upto 1866? Also even though timings for 1866 are 9-9-9-27, at the slower speed of 1333 timings are identical to my Crucial bog standard DDR-1333 at 9-9-9-24, I was expecting something a little better given the price premium on like for like memory speeds, so what did I pay extra for? Is the extra money just gone on a yellow sticker and some go faster heatsinks?
When this memory is put into an Ivy Bridge system I presume it is going to be recognised as DDR3-1333 memory, and not DDR3-1600 as there is no JEDEC setting in the SPD? The other option then is to use the XMP profile which is 1866, exceeding the official DDR3-1600 support and entering into the realms of the over clocker and hope when pushed it all works okay. I guess I'm going to have use manual settings to get support for 1600, but what would these be?
I'm disappointed as it just seems to me I've bought bog standard memory at a premium price that Crucial 'hope' will overclock to 1866.
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02-18-2012 09:53 AM
What is shown in CPU-z SPD tab, can you show us please and thanks?!
JEDEC timings and speed for 1333MHz isn't going to change as that is a standard, even in faster memory, so what you see there is to be expected.
You paid for the highest speed and timings, that performance and of course the heat spreader will be where the money was spent. You will of course be able to manually set timings at any speed, so if they are rated at 1866 using 999-24 timings, you can probably safely run 888-20 or 777-18/20 at 1333MHz (Maybe even 666-18, might need more voltage there though). For 1600MHz, I'd expect 888-20 is probably a reasonable expectation at default voltage, maybe 777-20/24 with enough of the proper voltages (Outside of spec on QPI/Vtt and Memory voltage)
Yes, on IVY and SB/SB-E and even older P55 / P67 / Z68 / X58 you would need to enable the XMP profile for 1866Mhz or manually set that yourself. All DDR3 memory is standard 1333Mhz or less, and is tested to perform at the intended specified amount for the kit in question. This is standard across all memory brands and speeds (Even kits rated at 2400+ are standard JEDEC 1333Mhz memory chips, just binned and tested to perform at 2400 and would need set via XMP or manual user adjustments)
Please post an image of CPU-z SPD tab so we can all see what were discussing here, thanks!
02-18-2012 10:29 AM - edited 02-18-2012 10:30 AM
Thank you for the reply. I have this data from CPU-Z which I've attached below, it seems to show XMP profiles with lower latencies. I understand about the JEDEC standard and timings, but isn't DDR3-1600 a JEDEC standard as well?
I guess what I'm getting at is are the memory chips manufactured to work at 1600, or are they just bog standard DDR3-1333 chips that just happen to come from a good batch and so to run at these speeds are actually pushing them, with a resulting lower tolerance for stability?
Crucial have bog standard DDR3-1600 memory at CL11, I assume these work automatically as they are JEDEC rated at 1600? Yet I've bought a premium product that to my eyes appears to be standard DDR3-1333 which Crucial hope will overclock?
Thanks for your time.
DIMM # 1
SMBus address 0x50
Memory type DDR3
Module format UDIMM
Manufacturer (ID) Crucial Technology (7F7F7F7F7F9B0000)
Size 4096 MBytes
Max bandwidth PC3-10700H (667 MHz)
Part number BLT4G3D1869DT1TX0.
Number of banks 8
Nominal Voltage 1.50 Volts
XMP revision 1.3
JEDEC timings table CL-tRCD-tRP-tRAS-tRC @ frequency
JEDEC #1 6.0-6-6-16-22 @ 444 MHz
JEDEC #2 8.0-8-8-22-30 @ 592 MHz
JEDEC #3 9.0-9-9-24-33 @ 666 MHz
XMP profile XMP-1866
Voltage level 1.500 Volts
Min Cycle time 1.071 ns (933 MHz)
Min tRP 9.43 ns
Min tRCD 9.43 ns
Min tWR 15.00 ns
Min tRAS 28.14 ns
Min tRC 49.50 ns
Min tRFC 160.00 ns
Min tRTP 7.50 ns
Min tRRD 6.00 ns
Command Rate 2T
XMP timings table CL-tRCD-tRP-tRAS-tRC-CR @ frequency (voltage)
XMP #1 6.0-6-6-18-32-2T @ 636 MHz (1.500 Volts)
XMP #2 7.0-7-7-21-37-2T @ 742 MHz (1.500 Volts)
XMP #3 8.0-8-8-24-42-2T @ 848 MHz (1.500 Volts)
XMP #4 9.0-9-9-27-48-2T @ 954 MHz (1.500 Volts)
XMP #5 10.0-10-10-30-53-2T @ 1060 MHz (1.500 Volts)
02-18-2012 11:14 AM - edited 02-18-2012 11:16 AM
Yes, JEDEC has a 1600 standard, but it is rarely/never used by manufacturers, I've never seen it in the hundreds of DDR3 sets I've tested and used. Same applied with DDR2, most were all 667Mhz or 800Mhz, and then anything above that or with specical latencies would have to be set via SPD, EPP, or user adjustments. The reason for this 667Mhz DDR2 and 1066 or 1333Mhz DDR3 is these are the highest officially supported speeds by current Intel motherboards, above that is always officially considered overclocking (You'll see more in the link at the end).
I'm sure the kit you purchased is tested to perform fine at 1333, 1600, and of course 1866 too, rest assured! I'm not sure about the CAS 11 1600 kit you mention, ir may or may not have programmed JEDEC 1600 settings, but it surely includes XMP 1600, or SPD settings at the same, as that is more the mainstream motherboard programming these days.
Thanks for the info from CPU-z, as you can see there are many standar XMP pre-programmed timing and speed tables, you should be able to use any of those with ease on most any recent generation Intel motherboard (AMD may or may not require some tinkering or adjustments to run certain speeds or timings).
I see XMP programmed settings @ (And those may not be exact MHz when selectable in the BIOS):
Main XMP-1866 (933Mhz) @ 9-9-9-28 (1.5V)
^^ This profile, and the following, will also likely run at the standard command rate of 1T, 2T seems to be a normal pre-programmed setting as well (For compatibility and initial startup, may also be part of the JEDEC speficications they must follow?)
XMP #1 - 1272Mhz @ 6.0-6-6-18-32-2T @ 636 MHz (1.5V)
XMP #2 - 1484Mhz @ 7.0-7-7-21-37-2T @ 742 MHz (1.5V)
XMP #3 - 1696Mhz @ 8.0-8-8-24-42-2T @ 848 MHz (1.5V)
XMP #4 - 1908MHz @ 9.0-9-9-27-48-2T @ 954 MHz (1.5V)
XMP #5 - 2120MHz @ 10.0-10-10-30-53-2T @ 1060 MHz (1.5V)
See here for MSI's thoughts on the DDR3 JEDEC / EPP / XMP, ect confusion