I am building a rig and I need help understanding what memory I should be getting.
My rig is documented in copious detail here: http://www.tomshardware.com/forum/297471-31-gaming-beas...
But, in short, it is based around i7-950/GTX480. My aim is to play most games at 60fps. I have chosen the GA-X58A-UD5 (ver2.0) mobo. I am seeking 12GB of RAM (not for games) in 3x4GB. The Mobo demands a triplet. I will, eventually, play around with overclocking.
Here's what I understand about RAM:
(i) The speed (1333MHz, 1600MHz, 2200MHz) is really only important if you have processing HUGE blocks of memory, such as video processing. Otherwise, you really won't notice a difference between 1333MHz and 1600MHz even in high-end gaming.
(ii) What is MORE important for usual use is the ability to quickly grab your blocks of memory and for this CAS latency is FAR more important, for it is CAS latency multiplied by the clock speed that determines how many nanoseconds it takes for your memory block to be accessed.
(iii) CAS latencies are expressed like 9-9-9-27 where higher is slower. So 9-9-9-27 is slow. 7-7-7-22 is 22% faster. 9-9-9-27 seems the lowest for 4GB memory modules, while 7-8-7-20 and 8-8-8-24 exist for 2GB modules.
(iv) So, when Corsair memory modules are described in the catalogue as Corsair 4GB 1600 C9 and Corsair 4GB 1600 C8, the C9 and C8 is referring to the CAS latency, the first number in the 8-8-8-24 sequence!! This explains why the C8 is 25% more expensive!! It's got faster access times.
(v) The three first numbers DO NOT add-up to the fourth number, but instead refer to the clock cycles to respond to a request, the clock cycles taken between activating the line and column of your data, the clock cycles to deaccess one line before the next can be accessed, and the cycles after one access before the next can be started.
(vi) These numbers are the ratings for a given memory module, but, though bios, you can mess with them. The cost? Stability.
(vii) If you're going to overclock, don't bother o/c-ing the FSB (the memory), concentrate on the CPU itself. (That said, some say you can, others say you can't, o/c the i7-950.)
(viii) The RAM frequency will be forced to sync with the FSB frequency. Which means that even if I install ddr3-1600MHz, that's just their maximum rated speed, which means they'll run happily at 1066MHz.
(ix) Triple channel > dual channel > single channel.
Are these facts accurate?
So, here's my questions, please:
1. The Gigabyte website lists a bunch of memory chips that are "verified" for the UD5 mobo. Because there's only THREE 4GB chips listed (Hynix DDR3-1333 H9C and the Kingston KHX1600C9D3K3/12GX), how decisive should this list be for my selection? Should I stick rigorously to these (even tho' Hynix aint in Oz)?
(The Samsung DDR3-1066 K4B2G0846B HCF8's are also listed as 4GB, but they're 2GB according to Samsung, as designated by the "2G" as the 4th and 5th letters. Samsung don't seem to have 4GB modules out yet?! Maybe.)
2. On Tom's I have read someone make the following claim: Core i7 doesn't use more than 1333mhz in a 3 memory chip config or 1066mhz in a 6 memory chip config without overclocking in any case.
I am not sure I really understand this statement other than to affirm that there's no point me buying higher than DDR3-1066MHz since, ultimately, I will probably buy another three DIMMs in a year or two. But IS IT TRUE????
It would certainly explain why the UD5 mobo only supports 800, 1066 and 1333 MHz modules. (I assume that's the only options in the bios?) Oh, and 2200 MHz. O_o
3. Are Kingston up there, quality-wise, with Corsair, OCZ and G.Skill for memory? For that matter are G.Skill even up there?
1) Verified vender list help but doesn't mean ram that isn't on the list won't work. If you find some ram you like, you can look on the list first, then look for some reviews or thred with that mobo and the ram you picked. Most times there will be some feed back on the mobo/ram combo your thinking about buying.
2) You can most certainly run ddr3 1333 and above without issue
3) I would actually put G.Skill right up at the top of the list. They make some nice ram and memory products in general. Kingston has been around for quite some time and is a reliable company as is corsair, I would rate OCZ last out of the 4.