Is my Memory's Latency wrong???

andytg7

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I was using CPU-Z today to check out some information about my CPU, when I noticed something that didn't look right. My memory's latency, or at least I think that's what it is. This is the memory I have:

http://www.corsair.com/_datasheets/TWIN2X2048-6400C4PRO.pdf

According to that, my memory's latency should be 4-4-4-12 at 2.1V.

However, CPU-Z doesn't seem to agree.

http://picasaweb.google.com/AndyTG7/Temp/photo#5154014494715723554

Am I right in that my memory is running at the wrong latency? If so, why could that be? And how can I fix this?

My motherboard is an Asus P5W DH Deluxe running Bios version 2004.
 

andytg7

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Badge - I have power saving features running in my Bios, such as Intel Speedstep and the other I believe is called C1E or something like that. Will changing the timings cause any issues with them? Are they the reason my timings are off?
 


Memory timings and voltage have nothing to do with speedstep or power saving. Corsair specs say your DIMMS will run at 4-4-4-12 at 2.1v. You will have to set those values in BIOS manually. Like I said, depending on your sustem, hopefully your system will run with the tighter timings. If everything is stable with your system and you are fine with it's current performance, 5-5-5-15 is fine. If you click on SPD on your CPUZ reading, 4-4-4-12 at 2.1v should be an option listed there. Corsiar has programmed your DIMMS to 'boot' at lower voltages at 5 CAS LAT (SPID). You will have go into BIOS and make the memory timings and voltage adjustments to get peak performance out of the Corsair DIMMS you have. HTH.
 

tonymarcus

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Hello Badge,

Why are the settings in the SPD not the same as corsair have spec'd the ram at. On my old P4 system I have DDR 1 Corsair XMS 3500 which the specs are Cas 2,3,3,7. In the SPD the settings read :-

Frequency 166Mhz 2,4,3,7 and Frequency 200Mhz 2.5,4,4,8

Does the above mean if I run my Memory at 166Mhz then I should use 2,4,3,7 and if I run it at 200Mhz then it should be 2.5,4,4,8.

When I build my new rig I see that people suggest lowering timings if you over clock Ram faster than it is specified to go, if you keep it with in spec do you just set it to recomended settings.

e.g I buy some DDR2 PC6400 which has recomended settings of 4,4,4,12 I run ram at 400Mhz (800ddr) do I just use the recomended settings, if I overclock the ram then I presume I lower settings (5,5,5,15) them memtest the settings.

Thanks

Tony
 


This should answer your question.

http://www.crucial.com/kb/answer.aspx?qid=4050

When I build my new rig I see that people suggest lowering timings if you over clock Ram faster than it is specified to go, if you keep it with in spec do you just set it to recomended settings.

It has been my experience to do just the opposite. If you have a heavy overclock going on (increase in system FSB) it could make the difference in having a higher overclock potential if you LOOSEN the memory timings to create some 'slack' where data transfer between the RAM/CPU is concerned. In other words, if your memory is set to 4-4-4-12 and you hit a wall at a certain overclock, try loosening the memory to 5-5-5-15 and you should get past the 4-4-4-12 'wall' and achieve a higher overclock.
 

tonymarcus

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Hello again Badge,

Thanks for the link that answered it spot on. When I said lower timings I meant losen. When you losen the timings so you losen all 4 of them together 1 notch or each one individually.

e.g ram is spec'd as 4-4-4-12, with over clocked memory my memory is failing mem test do I change to 5-5-5-15 all at once or change one at a time then mem test each change ??
 
Well, set the memory's timings and voltage to what the manufacturer advertises they will run at. If you are O'cing and hit a wall, loosen them up either one at a time or all at once whatever works. Exessively overvolting the RAM can lead to a shortened life span and ultimate failure of the RAM to work at all.