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"Optimal" settings with SLI memory and voltage questions


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Hey there.

First off, I thought about posting this question in the warranty section because I have a few questions about my memory that I just got back from an RMA (Post ID # = 278166) but this new ram seems to work fine and I have a few questions about setting it up and wanted some advice from the experts!


I have the 8888C4D Dominators on the Asus Crosshair (nf590sli). When I set the memory in the bios to SLI "Optimal", the bios gives me the following settings: 4-4-4-12-2T, 800mhz, 2.00 volts DDR voltage, and 0.99V DDR term volts (I included this because I got an alarm with Asus probe before on DDR term volts).


However, when I run memtest vers 1.7, memtest tells me that my ram is running at 480mhz (with as you know is 960mhz). This is different than what the bios tells me (800mhz). I understand (??) that the memory bus can be clocked differently than the cpu bus, but I can find no mention in the bios of 480 or 960mhz...just when I run memtest. Everywhere in the bios I look that has any type of bus speed listed for ram or cpu, it is 800mhz. I have not used any other program or utility to verify this, as I am more concerned with getting getting the ram settled with memtest first.


I guess my questions are:

1. What is going on with the "Optimal" settings, and are they covered under warranty? I don't want to do any crazy overclocking, but if these modules are "supposed" to work like this than I'll go with them. (I'll grudgingly take the extra performance ;) ) I really don't want to overclock the cpu though.

2. Why do the settings "look" different to me in the bios and in memtest? Again, I don't want to damage the modules/mb/cpu.

3. Are there enough / proper volts for my ram? They are rated at 2.4, but the bios automatically sends 2.0, and what is this DDR term volts? (Asus' website seems to indicate contacting the manufacturer)

4. I don't have the Dominator fans installed yet. Should I use the fans for this "optimal" setting? Can tight timings (assuming nothing else is pushed too hard) damage the modules if I adjust them manually?


Thanks for any help, and my apologies for the many questions. I want to get this system working well with the stuff I have, without damaging anything. And you guys in here are the best!

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First thing, the memory frequency is actually a divider seting off of the CPU frequency so the main question is what is the CPU frequency set to?

And the tested settings for these modules are listed in "Dominator Qualifications and Testing" I would suggest using this as reference when you setup your Bios and yes you need to be using the fan at 2.4 Volts!

I would also check the test report for your MB.


But as I remember this MB will top out about 1080 Mhz.

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That was quick...thanks!

I am using the x2 4600+ (2.4ghz).The CPU freq is 200 in the bios (multiplier and memory clock freq are both "Auto" in this same section of the bios). Checking again, however, the bios still tells me that the DDR bus speed is 800mhz, and memtest tells me bus is 960mhz.


I adjusted the DDR voltage from 2.0 (automatically set) to 2.1 (which seems to increase the DDR termination volts to 1.05 automatically). If this works fine do I still need the fans? (If i go any higher volts I will def use them...I figured since other dominators don't use them at that voltage these won't either...but if I am advised to use them anyways then no problem!).


Looking at the links you listed, my exact setup wasnt used, but the fsb listed were 1111mhz or higher (which I won't be using). There were TWIN2X2048-6400C4D's listed with my board, which I think are similar to my modules. The maximum tested settings listed for these modules seem to match the "Optimal" settings that memtest seem to be matching.


My main concern is why would the bios tell me one thing and memtest another? (or am I too noob and are missing something!)


Thanks again.


ps. after a little thought, I added the airflow fan to the ram anyways. It just meant that I had to use my stock cpu heatsink instead...my typhoon was blocking the fan installation)

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Hey. Tell me if I'm right (like I said...I'm a noob... never overclock :o: );


Using cpu-z, it looks like the cpu isn't overclocked, but the ram fsb is. With the defaults compared to the "Optimal" settings, the cpu core speed stays the same, but the multiplier decreases from x12 to x10, the bus speed increases from 200 to 240, and the HT link increases to 1200.


In the memory section, the frequency changes from 400 to 480, cpu/6 changes to cpu/5, and the latency settings are basically unchanged (4-4-4-10-23 2t to 4-4-4-10-26 2T).


I guess this means that the "Optimal" settings do not overclock the cpu, but the ram? (which is guess is not actually overclocking since these are rated at 1111, and I am running at 960). Will this not damage my hardware, since these are settings programmed into the hardware itself? (I DO have the airflow fans installed).


If this is not an overclock, will I get better performance on an 800mhz bus with tighter timings?


Thanks for the patience and the help!

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