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Why is my 800Mhz Ram showing up as 400?

Last response: in Systems
February 1, 2007 2:07:38 AM

Hey guys, need an answer. Why does cpu-z show that my ram is running at 400mhz when it is 6400(800Mhz)? I have Athlon 64 3800+(orleans) with Gigabyte M5SLI-S4 mobo and Wintec AMPX 512mb DDR2 6400 stick of ram. You can find all these on newegg. I just have 1 stick of 512mb if that helps.

I have no option in BIOS to change it either, in the Motherboard Intelligent Tweaker, Gigabyte OC tool.

Also, could this be casing windows to crash in the middle of a program to BSOD? It shows the code, but windows doesn't know what it is.

Thanks guys.

More about : 800mhz ram showing 400

February 1, 2007 2:26:56 AM

Because that is the correct speed. The rated speed for DDR RAM is 2x the actual speed.

Think of a sine wave. RAM prior to DDR would only work on the "up wave", during the "down wave" no data is transferred. DDR RAM transfers data on both "up" and "down" therefore the rating is twice the actual speed.
February 1, 2007 2:29:04 AM

CPU-Z shows actual clock speed of the RAM. 800 MHz is effective speed to due DDR or Double Data Rate, ergo 400 x 2 = 800.
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February 1, 2007 12:48:36 PM

O, ok. I didn't know that. thanks!
February 1, 2007 11:15:48 PM

O, ok. I didn't know that. thanks!

You're welcome. Glad to help. :D