P6X58D-E help w/ XMP profile + RAM upgrade

With the same board, what XMP did for the 2x4gb corsairs i got is that, it set it to the default clocks (instead of running at 1066mhz, it ran at the default 1600mhz). I would first check the speed at which your RAM is running then check if its XMP compatible.

XMP has no effects on video card OC far as im concerned. This is only a speculation but since XMP sets the clocks automatically im guessing that if you ever want to OC the CPU you should start off with the speed at 1066. Since raising the bclk will raise the clock speed for the RAM as well.
Edited by Mello - 1/12/11 at 7:25am

What task you trying to perform?
Increasing RAM amounts is not always the solution for speed.
BTW 'not under load' is idle

The XMP profiles are basically just a quicky overclock to bring your RAM speed up that may or may not work all that great for your system. Due to having to work for lots of people they can't be all that optimized and usually are pretty ugly overclocks. Better to just set what you want manually.

A quicky RAM course.

The RAM frequency is based on the baseclock (BCLK) multiplied by a memory multi. In your specific BIOS the multi is invisible and it will just give you the frequency choices available based on the baseclock. Raising either BCLK or the multiplier will raise the DRAM frequency.

UCLK Frequency should be twice the DRAM Frequency.

Memory timings can and in most cases should be set manually. The ones to worry about start at the top of the list and are in order for the timings listed for your RAM. While the command rate (1n or 1T or 2N or 2T) can be found a little farther down the list. Just set them to the spec timings for your RAM to start with.

Overclocking the memory by raising the frequency or lowering the timing can and most likely will take some added voltage to keep stable.

Uncore voltage as it is generically called or QPI/DRAM Core Voltage in your BIOS has to be within .5v min. of the DRAM BUS Voltage. A good safe range would be 1.15v- 1.35v. This is a pretty touchy voltage and not having enough by a very small amount can cause instability pretty quick. Having too much I've found can cause instability also. Among other things this voltage powers the Internal Memory Controller (IMC) in the CPU FYI.

DRAM Bus Voltage pretty much can be thought of as the voltage powering the RAM itself. It is best to just set this voltage to what is spec for your RAM. Raising it over spec can help power higher frequencies or lower timings beyond spec. Intel stock for this voltage is 1.5v and it is common to see RAM that are spec up to 1.65v.

If you overclock the CPU ( frequency determined by BCLK X CPU Ratio) it is best to start out with the lowest memory multi 2:6 (or x6). This somewhat seperates the CPU from the memory and you can test for stability of the CPU and proper vcore (CPU Voltage) without the uncore side of things causing it's problems. Then after you get stable you can bring the multiplier and RAM speed back up, test some more and dial in the voltages for the higher memory speed.

For more info I've found Mihallen's guides to be a pretty good starting point. http://www.techreaction.net/2010/09/...-and-gulftown/. You can also click on the Asus link in my sig for a thread with tons of info on overclocking with your motherboard. Here is a handy voltage guide also http://www.evga.com/forumsarchive/tm...09&mpage=1&key . The guide to 4.0 has some good info as well even if you are not looking to hit 4.0. http://www.overclock.net/intel-cpus/...920-930-a.html
Edited by ~sizzzle~ - 1/12/11 at 8:25am

Assuming you are using Windows 7, Windows caches a large amount of unused RAM. This can make it appear that RAM usage is higher than what it is.

Yes raising the RAM frequency over Intel Stock is overclocking. At least memory overclocking and the best way to get 1600Mhz RAM speed would be to overclock the CPU as well. By buying 1600Mhz RAM you bought RAM that is good for overclocking. They list it as tested and guaranteed to be stable at 1600Mhz. Not really this RAM will run at 1600Mhz straight out of the box.

That is where the XMP comes in. More of a marketing stratagy to sell you high speed RAM. Really it is just push button memory overclocking. When you select a XMP profile it auto changes the settings for you. Just not always to the most ideal settings.