Corsair DDR2-6400CL4 timings off

Axle

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I've done a search and haven't found this error, so...

As you can see from my Sig I'm running a C2DE6600 (stock speeds), MSI Mobo and 2xCorsair PC2-6400 1Gb 4-4-4-12 CL4 ram.
My friend and I both got all 3 of these same items and both machines report; 5-6-6-15 when booting and using detected settings.
I can force the two systems to use 5-5-5-15 and it still runs but if I try to use the 4-4-4-12 as written on the DIMM's it just hangs and gives up.

Am I going mad or should they run 4-4-4-12!? If 5-6-6-15 is how it's supposed to be why isn't that on the DIMM's?? Have we got a rubbish MoBo or is the RAM to blame?

Thoughts please?
 

1Tanker

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Apr 28, 2006
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I've done a search and haven't found this error, so...

As you can see from my Sig I'm running a C2DE6600 (stock speeds), MSI Mobo and 2xCorsair PC2-6400 1Gb 4-4-4-12 CL4 ram.
My friend and I both got all 3 of these same items and both machines report; 5-6-6-15 when booting and using detected settings.
I can force the two systems to use 5-5-5-15 and it still runs but if I try to use the 4-4-4-12 as written on the DIMM's it just hangs and gives up.

Am I going mad or should they run 4-4-4-12!? If 5-6-6-15 is how it's supposed to be why isn't that on the DIMM's?? Have we got a rubbish MoBo or is the RAM to blame?

Thoughts please?
What vDIMM are you running them at? They will probably need~ 2.1v to run @ that speed and timing. The high latencies are set in the SPD to run @ 1.8v(JEDEC standard), for compatability/ reasons. That way the modules will at least boot up in most motherboards, and then the speed/timings can be adjusted once in the BIOS. GL :)
 

Axle

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Hmmm...I've not tweaked anything to do with voltages...
So you're saying in effect the system won't supply more power automatically to run the 4-4-4-12 timings, I need to tweak this vDIMM SPD voltage to get the most out of them...which will increase heat.
 

1Tanker

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Apr 28, 2006
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Hmmm...I've not tweaked anything to do with voltages...
So you're saying in effect the system won't supply more power automatically to run the 4-4-4-12 timings, I need to tweak this vDIMM SPD voltage to get the most out of them...which will increase heat.
Yes, if you run the RAM @SPD setting, that's the "safe" settings programmed into the RAM. You have to disable SPD, which will leave you free to adjust timings, memory dividers, and RAM voltage. You will likely have to raise the voltage to ~2.1v. That shouldn't be a problem for your RAM... (as long as they have heatspreaders attached). They may run a touch warmer, but nothing to worry about.
 

Mondoman

Splendid
Axle,
Nothing's wrong with your RAM. This post will explain things:
http://forumz.tomshardware.com/hardware/modules.php?name=Forums&file=viewtopic&p=1249881#1249881
As 1T said, your DIMMs are running at the pre-programmed standard SPD settings. The 4-4-4-12 timings are only guaranteed under non-standard, manufacturer-sanctioned overclocking conditions. If you go to the Corsair website, you can find the spec sheet for your specific model number, which will list the higher voltage at which the spec performance is guaranteed.
 

bydesign

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I have the Corsair DDR2-6400CL4 and my MB detects them as 5-5-5-16. However I need no voltage adjustment to run at 4-4-4-12. Perhaps the Bios is auto adjusting that for me I'll have to check.
 

bydesign

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I have the same ram and it auto detects at correction 5-4-4-12. I have it set to 4-4-4-12 at 1.80V and have no issues with Asus P5W DH. Just checked.
 
G

Guest

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If you left the voltage at Auto there is a chance the motherboard does it for you.

Also so ram will manage to do the timming specified at lower voltage. Also batch are better than other...
 

Axle

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I did as suggested and indeed 4-4-4-12 has been achieved.

Thanks for the advice

My MSI P965i Platinum is now running the ram at 2.1v.