I beg you forgive my ignorance but there's something i can't quite grasp. According to SB reviews, the maximum memory frequency supported by the memory controller is 1333Mhz; anything higher should be considered overclocking. If the memory controller is built in the processor and that controller regards 1600mhz as OC, how can it be that some motherboards (p8p67 pro for example) include 1600Mhz as a non-OC option? I'm asking because most issues with SB motherboards have been traced back to memories sticks. In fact, lots of people couldn't boot their pcs until they set their memory speed to 1333mhz. Maybe i'm wrong and motherboards do support that frequency as a non-OC setting, but then i don't understand how they do it and an explanation would be very welcomed. Thanks in advance !
1333MHz is the JEDEC standard for memory, and is the default frequency that will always boot. All the memory ICs sold are 1333MHz - they are just binned to select the chips capable of faster speeds, then sold at a premium (since the quantity is extremely low). The CPU memory controller will "allow" up to 2133MHz, but it requires additional voltages to parts of the CPU. Most people don't really understand memory overclocking to be honest - extra voltage in the VCCIO and VCCSA is required on top of memory voltage, and not every CPU will be capable of it even if it offers the option (as is the case in all overclocking). Your best bet is just to use XMP certified memory that's on the QVL list of the motherboard. When I was 'testing' SB I played through most of Crysis at the 2,133MHz setting + CPU OC at 4.5GHz. It can be done, but it needs patience and research
It's still confusing for me but i'll read a little more and try to think it again. However, if i did understand well, 1600mhz and higher IS overclocking even if the motherboard or memory controller allows it. Did i get it wrong ?
Pretty much, but if you buy XMP certified memory like Bindi says then you won't have to mess about with voltages for 1600MHz, and I don't think there is much that will take advantage of running it faster than that.
Yes, technically speaking. But Intel certifies this with XMP profiles that increase the necessary voltages to make it stable.
So if I enable the XMP profile on my Corsair Vengeance it should just work? I only ask because I am in the process of setting up a new SB build (2500K, Asus P8P67, Corsair Vengeance 8GB DDR3 1600 MHz CAS 9 XMP) and enabling XMP causes Windows to freeze up just before the login screen. Everything else was set to whatever the "Load optimized defaults" put it to - it was the first bit of tweaking I tried...
Try it with just one stick at a time and see if one of them is faulty. Oh and what voltage is your ram supposed to be and what does it say it is in the bios/windows?
It all boots ok at the default 1333 speed, I'll give that a go when I get home and perhaps try memtest as well - was trying it late last night and had to give up in order to be functional for work today Memory is rated at 1.5v which the bios at least was reporting correctly.
I've had windows built in memory test find faults where memtest could not. They will probably both pass at default speeds, if one stick boots into windows and the other doesn't then you know which one isn't up to scratch. Sometimes updated bios's have updated XMP profiles
I think I've got the latest bios - 1305 off the top of my head - it's a B3 board which only arrived yesterday. Thanks for the feedback, I'll have a play tonight and see if I can work anything out. I was just curious if XMP settings did just work or if sometimes it needed further manual tweaking.
I too am having some very silly issues with my memory. I have the Vengance 1600 CAS 8 and using the XMP profile it just blue screens in games. Pulling my hair out, im thinking my overclocks is crap ( prob is ) but no joy with it running at 1600mhz at all. Im not a novice overclocker ( nor a pro ) but it really is pissing me off. Was even thinking of selling the whole damn rig and just going back to my i5 750 because it was just no hassle at all. Speed of my new 2500k and the Asus p67 is great, any load i give it thou just crashes! Any help ,advice would be well appriciated. Yes i have the 1305 Bios under H50 cooler in a Antec P183 with Corsair 850 PSU ... Anyone can copy their settings from their overclock for my to try?
These boards are very new, and in the case of B3 shipped out in a rush, you will probably find that a BIOS up-date will sort this out, it has for me on a Asus P6H67 M and a P8P67 Pro.
I was thinking of getting this kit of ripjaws-x 1600mhz cas9 but i can find any mention to XMP. Does it have an XMP profile or should i search for another memories?? if that's the case, any suggestion will be welcome ^^'
I running that kit and it seems to be humming along just fine. Newegg had them on sale for $80 /w free shipping yesterday, so in about a week I'm going to be the proud owner of 16GB of ram
OK just spent a fruitless hour or so fiddling with things and it seems it's not just the XMP profile which doesn't work, it's the whole damned overclocking thing which is a general no-no. I can't even set the CPU ratio up to 38 with everything else on auto, it just hangs on the Windows splash screen just before the login prompt displays. FWIW I tried both RAM sticks individually in both slots to no avail. I couldn't even boot into Safe Mode. Found a post somewhere saying that clearing the CMOS might help with XMP, again tried that with no joy. With the XMP profile loaded and both modules installed it quite happily passed the Windows memory test. What the fudge? Any ideas? There's nothing in the Windows event logs to give me any clue. I R a confused, frustrated and rather sad bunny. edit: to prevent threadjacking further (sorry) I've started my own thread http://forums.bit-tech.net/showthread.php?t=205550
