DDR2 at 1066 MHz runs at 800 MHz

m3th0dman

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I bought this type of RAM http://www.valueram.com/datasheets/KHX8500D2K2_4G.pdf
Kingston 2x 2 GB, and I've tried many things to make them run at 1066 MHz.
The motherboard is Gigabyte EP45-DS3LR and supports DDR 2 1333+ and the CPU is Intel Core 2 Quad Q9550 with a FSB of 1333 MHz so they should be compatible.
O.S: Vista Ultimate x64

I have changed from BIOS the latency to 5-5-5-15 (was on auto) and the DRAM Voltage to 2.200 V (although it's shown in pink because a high voltage). Performance Enhance is on default (originally was turbo) and the SPD on auto.
After doing this, back in Windows using CPU-Z and Everest, still show me that the RAM runs at 800 MHz.
And on the module itself is written that it 2.3 V but not on the specs.

What should I do next?
 
You need to go in the bios and manually unlink the memory and change the speed or change ratio to FSB. Change that SPD from auto to manual. The options should be available after that.
CPU-Z should show 533 MHZ.
Test the memory for errors with memtest86+ finally.

 

m3th0dman

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You mean to put the FSB of the CPU to 1066 MHz, so the ratio should be 1:1 ? This would underlock the CPU/

I don't know which option to select on SPD; there are many options there, numbers followed by letters. I'll post latter the options.
 

MaDMagik

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Your FSB base clock is 333MHz, the option you need to choose in SPD is the one that multiplied by 333 will give 1066(or close to it) so most likely its going to be 3.20. My guess is 3.20B
 

m3th0dman

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Thanks MaDMagik, the SPD was the problem. I've putted on 3.20 B and everything works fine now.

What I don't get, is why when I check the SPD in CPU-Z it shows at the Max Bandwidth PC-6400 (400 MHz). Are they PC-6400 modules but ready for overlocking at 1066 MHz?
 

Mongox

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If CPUz is still not showing a 533 column in SPD, then you're still running as though you had 800s in the slots.

The key thing is in the spec sheet for the RAM - "Each module pair has been tested to run at DDR2- 1066MHz at a latency timing of 5-5-5-15 at 2.2V". Unless you send that RAM 2.2Vs then it's not going to run at 1066. I had to return my 1066 RAM recently because my M/B wouldn't push over 2.1Vs to it and it wouldn't ever show at 1066. But, most here would way that you're better off with a CL of 5 like you have now than giving that up to get 1066. I was stubborn and decided to go for 1066 anyway and gave up a better CL for it.

 

m3th0dman

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On memory menu, it shows me 533 MHz and it works fine. It also shows me 1066 MHz in BIOS and Everest, but in memory. In SPD shows me what I have written before.
 

MaDMagik

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Thats exactly what they are. I think 1066 was never made official standard by JEDEC, that is why you have 400Mhz and not 533 in SPD.
 

Mongox

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Again, without sending those modules 2.2Vs, you won't get 1066 from them. When I was using 1066 OCZs I never saw the 533 on SPD, just up to 400. Now that I have 1.8V RAM I get this. Again, the performance was likely better with the OCZ because they had lower CL at 400 than these do.

This screen shows my 533 JEDEC in SPD - well, actually 555. Never saw this with other 1066 RAM installed.

spd.jpg
 

Mongox

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Well, guess you're getting 1066 performance and as MadMagik said above, the SPD wasn't updated at the factory to show the mode. Seems unlikely that no SPDs have that byte set to 533 - I'm sure I've seen it elsewhere in posts since maxing to the SPD is common subject.

I'd say you've done what you can with these modules!
 
Do you want to overclock your RAM or do you want more performance?

Overclocking RAM does not have a significant impact on performance. It can, however, contribute to instability.

My recommendations:
Change the System Memory Multiplier to Manual. Select 2.00B for the multiplier. Now your memory frequency will be twice the FSB.

If, for example, you increase the FSB to 400 MHz, your memory will run at DDR2-800 speeds and your processor core will be running at 3.4 GHz (will need to add better heatsink and may need to increase voltage.

You will gain more performance by dropping the memory timing from 7-7-7-24 to 6-6-6-18 than you will by OC'ing the RAM and running it at 7-7-7-24.
----------
Overclocking since 1978 - Z80 (TRS-80) from 1.77 MHz to 2.01 MHz
 

tubers

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well you are very lucky.. i had my Kingston Hyper X 4 gb.. 2x2gb sticks..

2.2 Volts at 7-7-7-21-2T (i did set it to that since i saw it was CL7!)

and also before.. it only runs at 800Mhz.. but everything is fine now.. just hate the fact that i bought mine more than a year ago at 100 U$D.. for something thats not even a CL5 (5-5-5-16 at least)

lucky u
 

m3th0dman

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I just want to run the RAM at the designed frequency, I don't want to overlock and I'm more than satisfied with the current performance.

If I'll change the SPD to 2.00B, wouldn't the RAM run at 666 MHz? Will this have a better performance than now, running at 1066 MHz? If so, why?

I don't plan overlocking the CPU for now, because it runs any software at the current speed and oc may reduce life cycle.