Question regarding Memory Voltage and MB compatability

jerseytiger

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Feb 23, 2009
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I have a question about RAM voltage and DIMM Slot voltage.

I am looking getting this board:

http://www.giga-byte.com/Products/Motherboard/Products_Spec.aspx?ProductID=3166

The specifications say that they are 4 x 1.5v DDR3 DIMM Sockets

However when I go to the QVL for this MB many of the memory listed is not 1.5v, many are 1.65v or 1.9v modules.

http://www.giga-byte.com/FileList/MemorySupport/mb_memory_ga-p55m-ud4.pdf


The MB says that it can support 2200, 1600, 1333, 1066, and 800 DDR3 RAM, but I can't even find any 1.5v 2200 RAM and almost no 1600 RAM.


So I guess my question is can the voltage be higher than 1.5 or will this present problems?

 

ekoostik

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Do NOT get any RAM that runs higher than 1.65V. Intel rates that as the absolute maximum spec for running RAM without damaging your CPU or motherboard.

You may want to base the frequency of RAM (e.g. 1333 MHz) you select on your CPU. If you get an i7 860 or i7 870, you can run RAM up to 1600 MHz at stock settings. With an i5 750 or a Clarkdale CPU you can run RAM up to 1333 MHz, any faster requires OCing your CPU.

If you don't plan on OCing, you may still find 1600 MHz worth purchasing - for example, sometimes it is cheaper than similarly spec'ed 1333 MHz RAM.

Here's a couple articles I think you'll find helpful:
What speed to get for socket 1156: http://www.tomshardware.com/reviews/core-i7-870-1156,2482.html
Value DDR3 for Intel's P55 chipset: http://www.tomshardware.com/reviews/ddr3-4gb-p55,2462.html

In general, look for lower voltage RAM with the tightest timings (e.g. CL7) at your price range. The basic recommendation from the first article I linked to is "Make sure you pick a branded product of at least DDR3-1333 speed and timings of CL8 or faster". Give it a read and you'll understand why.
 

Dragonstar

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Regarding changing the setting for memory, what if the motherboard doesn't allow you to adjust down. I am using the Gigabyte 790X
t-UD4P motherboard it has set my voltage to 1.65 and looks like I can only adjust upwards.
 

ekoostik

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Dragonstar,

The RAM V warnings for not going higher than 1.65V apply to Intel 1366 and 1156 socket motherboards. I don't know as much about the working of the AMD boards so I'll let someone else answer. But it might be helpful to know, what RAM do you have? Please provide the complete model number and a link would be helpful, too.