Hi, My system has a Asus P5Q Pro motherboard and it is supposed to support 1200 MHz memory (PC2-9600). My new Kingston HyperX 1200 MHz memory arrived today, however it only shows up as 800MHz (PC2-6400). Any ideas what I'm doing wrong? The timings in the BIOS are set to Auto. Thanks Ryan
You may have to manually set the speed of the ram in the bios. Get on Kingston's website and have a look at what voltage they should be run at. Some higher speed ram will want more juice than lower speed stuff and the board is probably playing it safe and sticking to its own default settings. Silly question, is the Kingston ram the only ram in the system? If there are other sticks at a lower speed, it will (well at least it should) default to the lower detected speed and timings.
Memory is a dumb animal - it does what the motherboard and BIOS tells it to. Matt is right, you have to set the speed specifically in the BIOS, however 1,200MHz DDR2 is not an easy speed to reach - your limitation will likely be your motherboard. Kingston can sell it as a "1200MHz" part because it has been pre-tested to do 1200MHz in their lab - you pay the extra for the privelage of them basically hand picking the best parts. Investigate the P5Q BIOS memory multipliers http://www.bit-tech.net/hardware/motherboards/2008/05/28/asus-p5q-deluxe-intel-p45-has-arrived/3 (that review is ooooold now bear in mind - the BIOS could have changed significantly) and update to the latest BIOS as well (EZFlash works great). You'll probably need to overclock the CPU front side bus too, depending on what memory multipliers are available, and don't be surprised if other settings (mostly voltages) require adjustment too: VTT, FSB termination, CPU PLL + voltage if you increase its speed, DRAM training and DRAM voltage, and FSB straps. Try: FSB Strap = 400MHz, DRAM training enabled AI Clock Twister lighter to help the OC DRAM voltage and timings to what it says on the side of the DIMM. P45 was a complex beast unfortunately, but it's fun to learn and there's plenty of info on the net about tweaking it Unfortunately the P5Q Pro was not a hugely high performance motherboard - unlike Gigabyte UD5/6 and Maximus II Formula, and you'll get much better performance actually by cranking the CPU front side bus and keeping the memory timings low, at a lower memory speed. 1,200MHz CL5 memory will easily allow 1,066MHz CL3-4 which is just as fast. Core 2 CPUs have tons of cache to negate the heavy use of memory anyway.
Thanks, I will try all of this. FYI, it's 4x1gb kingston sticks (I did want 2x2gb ocz platinum @ 1200 but they're now discontinued). I would've thought that 1200mhz memory is just 1200mhz memory - why there is a need to me to manually set my bios and do overclocking baffles me, especially as it's a speed supported by the motherboard. I specifically bought quick memory so I wouldn't have to do anything with it. Bah humbug!
JDEC standards only allow up to 800MHz, faster than this just means you don't have to use strange dividers when overclocking
Memory is the "24MB/s internet" of the hardware world. It can do 24MB/s, but only if the conditions are right. Memory ICs are only sold at 800MHz DDR2 and 1333MHz DDR3: JEDEC specification. Companies bin chips to be capable of faster performance, and sell you pre-rated memory for a premium, but like all overclocking products: you have to do it yourself. The motherboard will automatically set itself to these JEDEC specifications in order for you to have a fully working system: you dont want to plug in the memory and have it not work at all. It's a failsafe system. DDR3 often has something called "XMP" technology on some motherboards/memory products, which holds the overclocked value pre-set in the memory itself. Selected within the BIOS and it's just a one click overclock: job done. Only Nvidia offered it for DDR2 under the competing "EPP" brand on nForce motherboards. Your Intel P45 won't support it and noone makes "EPP" memory any more either. To be honest, I doubt you'll reach 1,200MHz with four sticks of memory - the load on the memory bus will be too great. Your best bet is to set it to its rated voltage and reduce the latency. Even then, "performance" memory really does virtually nothing for extra performance: more memory is better than faster.
Well, I think that's all questions answered to be honest! Thank you very much all for all of your help. Love the site, and thoroughly enjoy the podcasts (*will be searching the isles for llama meat!*) Cheers all!
