Crosshair III AMD and 8 gig's OCZ ram

dhoke

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HI folks-

Is there any issues with booting this board with the full 4 x 2Gb of ddr3 1600 ram installed.
Should I boot with 1 or 2 sticks and fix the timings and voltages in the bios then add the remaining sticks? I am using OCZ Platinium DDR3 1600 AMD edition 7 7 7 24 (now repackaged as Special AMD Black edition). Do I need to loosen the timings or change other parameters to run 8 gigs. There are many conflicting opinions on this. Some say they have had no problems running 8 gigs at 1600 mhz with the above timings--other say this is not possible.

Thanks (note this ram (platinum ed.) is still out there but a bit hard to find. The Black Edition doesn't seem to be availible yet)
 

Mongox

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This is OCZ3P1600? First step is to make sure you're setting DRAM voltage to 1.9V minimum. Try 2 sticks and see if they come up as 1600 with auto settings. If not, try setting voltage to 1.95 and reboot. If not 1600, go in and manually set to 1600. Don't mess with timings yet.

If the two boot as 1600, add the other pair. If still going at 1600 - you can check the auto timings with CPUz and see if it picked up the SPD properly. If not, manually change it.

The board says 1600 only with OC. But not sure what they mean by OCing it - only manually adjusting the RAM speed? If so, above will work.
 

dhoke

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Hi Mongox--Yes I have 4 2-Gb sticks of OCZ3P1600LVAM4GK, 7 7 7 24 at 1.65 volts. I might be a noob here but are you saying tha I have to run all four sticks well over the stated voltage of 1.65 volts. Is this necessary to run these sticks at 1600 MHz, or the above timings, or both. 2 sticks should run at 1600 MHz with the above timings at 1.65 volts, right? Any help on this will be appreciated.
 

Mongox

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No, not at all. I was looking at OCZ3P16004GK http://www.ocztechnology.com/products/memory/ocz_ddr3_pc3_12800_platinum_edition
Not your OCZ3P1600LVAM4GK
http://www.ocztechnology.com/products/memory/ocz_ddr3_pc3_12800_platinum_amd_edition

I'm very glad to see these low-voltage models of OCZ Plat out there. Should be much better quality. Odd that these are labeled as AMD Edition, since the driving force behind 1.5V-1.65V RAM is the Intel standard for i5/i7. But it's great that these models are hitting the market.

Try all I said above and sub 1.65V as the starting voltage. Test two sticks at first, get them working at 1600. Then add the other two. You may find you need more than 1.65V, perhaps 1.7V when you have 4 in.

No, you don't have to run them at 1600. You can try them at 1333 with tighter timing and be happy that way. But, I'd see if I can get them running at 1600 regardless.

That's what I did with my RAM. It's rated at a speed of 1100, 1066 is the standard with 800 as lower speed. It works fine at 1066 or 1100, but I'm currently running at 820 with lower latency.

Read this from Wiki for basics of Latency
http://en.wikipedia.org/wiki/CAS_latency
Which is faster is up for debate. Most will say that DDR3 over 1333 is not going to run any faster in throughput than 1333. Here's an article to read - be sure to skip to the conclusions page.
http://www.tomshardware.com/reviews/memory-scaling-i7,2325.html