DDR3 1600, or is it?

[Hapx4.0]

About a year and a half ago i bought a Tri-Channel kit of G.SKILL DDR3-1600 PC3-12800

I've always wondered but never took the time to ask someone who knows. When i have my CPU set to its native settings (i7 920 @ 2.66) the ram boots as DDR3 1066

If i go into my BIOS and manually change my memory to 1600, it won't load windows.

If i under clock the memory, and bump up my CPU to 3.2Ghz, it puts my memory at 1600 and it runs just fine

How can i run my memory at 1600, while keeping the stock 2.66?

I have everything left on auto. Is it something to do with the auto volts?



Rig

Ram: G.SKILL 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Triple Channel Kit Desktop Memory
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231247

Mobo: BIOSTAR TPOWER X58A LGA 1366 Intel X58 ATX Intel Motherboard
Newegg.com - BIOSTAR TPOWER X58A LGA 1366 Intel X58 ATX Intel Motherboard

Cpu: Intel Core i7-920 Bloomfield 2.66GHz 4 x 256KB L2 Cache 8MB L3 Cache LGA 1366 130W Quad-Core Processor
Newegg.com - Intel Core i7-920 Bloomfield 2.66GHz 4 x 256KB L2 Cache 8MB L3 Cache LGA 1366 130W Quad-Core Processor BX80601920

Psu: PC Power and Cooling S61EPS 610W Continuous @ 40°C EPS12V SLI Certified CrossFire Ready 80 PLUS Certified Active PFC Power Supply
Newegg.com - PC Power and Cooling S61EPS 610W Continuous @ 40°C EPS12V SLI Certified CrossFire Ready 80 PLUS Certified Active PFC Power Supply compatible with core i7

 

[Slaymate]

Memory Feature / DRAM Timing Control

Memory Frequency / DRAM Frequency
This setting will be displayed as a Ratio (2:6, 2:8, 2:10, 2:12, etc...) or as a Multiplier (6, 8, 10, 12, etc...). If you are presented with a ratio then you simply take the second number and that is your Multiplier. At the default BLCK setting of 133 we see that each Multiplier corresponds to the following Speeds.
BLCK x Memory Multiplier = DRAM Frequency
133 x 6 = 798 (800 MHz)
133 x 8 = 1064 (1066 MHz)
133 x 10 = 1330 (1333 MHz)
133 x 12 = 1596 (1600 MHz)
133 x 14 = 1862 (1866 MHz)
133 x 16 = 2128 (2133 MHz)
So why do some manufacturers give us ratio's, just what is that all about? Using 2:10 as an example, for every (2 MHz of the BLCK) : the memory bus speed (increases by 10 MHz). So at the default BLCK speed of 133 MHz we have 66.5 sets of 2 MHz multiplied by 10 equaling 665 MHz.
(133 MHz/2) x 10 = DRAM Bus Speed
66.5 MHz x 10 = 665 MHz Bus Speed (This will match the memory speed shown by CPU-Z)
665 MHz x 2 = 1330 MHz (our memory is Double Data Rate, DDR, so we multiply by 2).

Memory Latencies
When you bought your memory it was rated to run at a certain speed (1333, 1600, 2000) in MHz with a pre-defined set of latencies (for example, 7-7-7-24, 8-8-8-24, 9-9-9-30). These latencies represent the following bios settings:

CL - CAS#Latency - refers to the column of physical memory in an array of capacitors ( a grid comprising of rows and columns) used in DRAM modules. The latency refers to the active amount of clock cycles that must be expended to take a request. Combined, CL sends data from the memory controller, has it read to the memory location, and output to the modules output pins.

tRCD - RAS to CAS Delay - The memory controller selects a bank, followed by a row location (using the Row Address Strobe, or RAS) and a column location using CAS. It represents the time in cycles for issuing a command and active read \\ write commands.

tRP - Row Precharge Time - Row Precharge Time represents the minimum allowable time taken between any active command and the read \ writes of the following bank on the memory module.

tRAS - Min RAS Active Time - Represents the amount of time taken between a row being accessed and deactivated. A tRAS row must be allowed to complete before being deactivated, setting this option too low can result in data corruption as the row is closed down too soon.

Depending upon your specific bios and the settings provided you may have multiple options available to adjust. Of those options we will only be looking at two (2) more of these.

tRFC - Row Refresh Cycle Time - This parameter determines the amount of cycles it takes to refresh a row in a memory bank, again if this is set too low it will cause corruption and set too high will result in a loss in available bandwidth, but increase stability.

CR - Command Rate - When the MC (Memory Controller) first tries to access memory, it has to latch onto a memory bank, known as CS (Chip Select). Then it proceeds to find the column (CAS), the Row (RAS), and then return the data to the CPU. Now, 1T means it takes 1 clock cycle to find a memory bank, vs. 2T where it takes 2 clock cycles to find the memory bank.

Even if your not overclocking my i7 Overclocking Guide has some more information that you might find useful.

 

[S0ULphIRE]

If you set it to 1600Mhz and it doesn't boot, it's probably because you've got the wrong dram voltage set. It needs to be 1.65v (most motherboards will only do 1.66v but that's fine)
Also, make sure your timings are 8-8-8-21

 

[Hapx4.0]

yea it don't have 1.65, i tried 1.64 and set the timings, but no go. ill try that...ty guys

 

[Hapx4.0]

Okay, tried that. No boot. it flashes the windows logo then reboots. snapped a few iphone photos, sorry for the quality

 

[S0ULphIRE]

Change the DRAM Bus Voltage to 1.66
Don't worry about the warning that pops up, it's what it needs to be set at.

 

[Hapx4.0]

Change the DRAM Bus Voltage to 1.66
Don't worry about the warning that pops up, it's what it needs to be set at.

I have no idea where i found that screen of the last picture, i just went through EVERY screen i could find to change the DRAM Bus Voltage to 1.66, but its not there....i fail lol

 

[Hapx4.0]

This seems like the only way it will run at 1600. If i OC the CPU to 3.2Ghz - its fine, but it gets warm lol

 

[S0ULphIRE]

derp, missed the fact that you were asking how you could run it while at 1600 while at stock 2.66Ghz
Use these settings:

BCLK: 133Mhz
Multiplier: x20
Then out of the list for your DRAM frequency you'll be able to select 1600Mhz

 

[Hapx4.0]

When i do that, it won't boot into windows. I tried manually setting the timings, and DRAM volts to 1.66V (Won't let me run it at 1.65V) and it won't boot into windows. I want to start "properly" overclocking so i need to read into this anyways but, it bugs me that for someone who would never want to deal with this, can't just buy DDR3 1600 and just put it in, and have it work.

Just ran LinX and it failed with the picture above. also got temps up to 80C