DDR2-667 Memory showing as 625Mhz

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Kaos Kid
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DDR2-667 Memory showing as 625Mhz

Post by Kaos Kid » Thu Jul 28, 2011 8:38 pm

While goofing around with an old Compaq board and 4GB of HP branded (Micron) DDR2-667 memory (PC2-5300), I noticed that in both AIDA64 and CPU-Z the memory shows as operating at 625 (312.5x2) instead of 667 (333.5x2). I can't figure out why it doesn't run at full speed, since they should be entirely compatible. I also see that the memory multiplier/divider is CPU-DRAM 9. Is there a good reason why it doesn't show as running at the full spec? The timings do show up as correct for 667 (5-5-5-15) so I'm not sure why, unless it is just a limitation of the Narra3 Compaq mobo. There are no bios updates available for it on the Compaq site. In fact, this mobo doesn't even have official WinXP drivers, Compaq only offers Vista drivers. I have WinXP 32bit installed, and am using the Nforce 15.26 drivers, which seem to work fine. Could they be the reason? Note: This is an OEM bios that doesn't allow any changes to FSB or memory configs, so I'm stuck with defaults.

Another question: If you had the choice between either...

1) 4 x 1GB of DDR2-667 running at 625Mhz @ 5-5-5-15 (dual channel)

2) 1 x 1GB of DDR2-800 running at 800Mhz @ 5-5-5-15 (single channel)

3) 2 x 512mb DDR2-800 running at 800Mhz @ 6-6-6-18 (dual channel)

Which would you choose for a box (with the OEM Compaq) that would basically be an internet surfer? I'm not sure that having 4GB is really going to help that much, and with the 32-bit limitation not all is assignable anyway. I did try putting the 2x512mb of DDR2-800 in the first two slots and the 1x1GB of DDR2-800 in the 3rd slot, but it dropped all the memory to PC2-5300 in the bios, and put all the timings to 5-5-5-15, so it seemed the same as if I would have just used 2x1GB of the actual DDR2-667. I would have thought that it would have stayed at PC2-6400 but loosened the timings of the faster RAM to 6-6-6-18 instead of keeping the 5-5-5-15 and lowering the clock speed. Can anyone shed some insight on this?
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Re: DDR2-667 Memory showing as 625Mhz

Post by skier » Sat Jul 30, 2011 7:45 am

who cares about speed, with less than 2GB of memory i dont find computers ever usable for anything, use 2x1GB ddr2 667 at 625 and call it a day.
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