Bootcamp: RAM working at half speed (late 2012 27" iMac)

[vingi]

After succesfully installing Bootcamp with Windows 7 Professional edition on my new iMac (see sig), I was running some tests to compare performance between MacOSX and Windows 7 (Bootcamp).

When running Geekbench, I noticed something odd: my RAM (Kingston KTA-MB1600/8G) is listed running at 1600 MHz under MacOSX, while it's listed as running at 800 MHz under Windows 7.

Anyone else noticed the same (with other types of RAM)?
Any thoughts on the cause (driver related issue)?

Links:
Geekbench score MacOSX: 13,126
Geekbench score Windows 7: 11,694

 

[drambuie]

Have you noticed the difference in memory perfomance in the two Geekbench reports? OS X reports 7688 and Windows reports a faster 8116. I would say that the RAM is running at 1600MHz under Windows. Windows Geekbench is obviously reporting the memory clock speed, which would be 800MHz for 1600MHz DDR3 RAM. Double data rate, (DDR), RAM runs at 2x the clock speed. CPU-Z will also show a RAM clock speed of 800MHz.

 

[vingi]

Ah, I see you are right judging on the memory scores. Odd that the RAM speed is listed differently, but that might be an OS related display option.

The main difference between the MacOSX and bootcamp/windows scores seems to be processor floating point performance.

Thanks for the input.