Need help with RAM Specs for my motherboard!

[reyesz3]

i was shopping around for some DDR3 RAM and came across the PC3 numbers, does anyone know what these mean? at first i thought it was something to do with the slot but i think they correlate to the RAM Frequency but i could be wrong :L

my motherboard currently supports :
4 x DIMM, Max. 32GB, DDR3 2133(O.C.)/1866/1600/1333/1066 MHz ECC, Non-ECC, Un-buffered Memory
Dual Channel Memory Architecture

...According to the Asus Website

so i decided to do some research and found that the crucial website shows my motherboard supports these "frequencies" or what ever they are:
DDR3 PC3-10600
DDR3 PC3-12800
DDR3 PC3-8500
DDR3 PC3-14900
DDR3 PC3-17000
DDR3 PC3-14400

most 1866mhz memory uses PC3-15000 and since that isnt compatible with what Asus say does that mean i can't use that memory at all for my motherboard or is it just limited to a certain frequency (somewhat like what backward compatibility does).

oh and i'm planning to get 2x4GB 1866mhz RAM for my motherboard if anyone has any suggestions also

need help guys thanks in advance!

 

[Eximo]

The PC values are marketing terms more or less based on bandwidth rather then frequency. Helps separate DDR2 from DDR3 in the stores.

As long as you stick to something similiar to the memory found in the qualified vendor list (QVL), you can find this on the ASUS support site, you should be fine.

 

[reyesz3]

The PC values are marketing terms more or less based on bandwidth rather then frequency. Helps separate DDR2 from DDR3 in the stores.

As long as you stick to something similiar to the memory found in the qualified vendor list (QVL), you can find this on the ASUS support site, you should be fine.

the latest update for the QVL was last year is it possible to find a more updated list for newer RAM modules?

 

[gbryan101]

The number PC3-XXXX is the peak transfer rate. What most people use is the data rate (e.g. 1600MT/s). The data rate is double the IO Bus clock rate and the peak transfer rate is eight times the data rate. This is all from the JEDEC standards: http://en.wikipedia.org/wiki/DDR3_SDRAM

1866*8= 14928 which is 14900. It should work on your board. If it doesn't, you machine probably won't boot, at which point you go in and try a lower frequency.

 

[Eximo]

It is intended as a guide, and often times you will find similiar or exact model numbers still in production. Primarily you should be looking at the voltages, frequencies, and timings. As long as you get something that matches that exactly, there is almost zero percent chance of it not working.

With XMP profiles it is also quite easy to just plug them in, set to XMP mode, and it will basically set itself.

 

[reyesz3]

The number PC3-XXXX is the peak transfer rate. What most people use is the data rate (e.g. 1600MT/s). The data rate is double the IO Bus clock rate and the peak transfer rate is eight times the data rate. This is all from the JEDEC standards: http://en.wikipedia.org/wiki/DDR3_SDRAM

1866*8= 14928 which is 14900. It should work on your board. If it doesn't, you machine probably won't boot, at which point you go in and try a lower frequency.

so basically according to JEDEC all 1866Mhz Modules should be PC3-14900? which is compatible with my motherboard as far as the Asus website shows.

does that also mean ANY 1866Mhz module RAM will be compatible with my motherboard? as long as the module is Non-ECC and Un-Buffered

 

[reyesz3]

It is intended as a guide, and often times you will find similiar or exact model numbers still in production. Primarily you should be looking at the voltages, frequencies, and timings. As long as you get something that matches that exactly, there is almost zero percent chance of it not working.

With XMP profiles it is also quite easy to just plug them in, set to XMP mode, and it will basically set itself.

i thought the XMP profiles are only compatible with Intel boards, i have an AMD :L

 

[Eximo]

Indeed, XMP is only natively supported by Intel boards. You hadn't specified what kind you had.

In that case, you take the numbers provided by the vendor and enter them manually. Or stick to the QVL memory.

Generally I just go down the list, find the speed/size I am shooting for and go shopping for kits.

Pick a brand, color scheme, or something and just start comparing them to the QVL. When you find something with a very similar model, brand, speed, latency, and size you have it.

Most recently I bought directly from the QVL since I bought the board on release week.

 

[gbryan101]

The number PC3-XXXX is the peak transfer rate. What most people use is the data rate (e.g. 1600MT/s). The data rate is double the IO Bus clock rate and the peak transfer rate is eight times the data rate. This is all from the JEDEC standards: http://en.wikipedia.org/wiki/DDR3_SDRAM

1866*8= 14928 which is 14900. It should work on your board. If it doesn't, you machine probably won't boot, at which point you go in and try a lower frequency.

so basically according to JEDEC all 1866Mhz Modules should be PC3-14900? which is compatible with my motherboard as far as the Asus website shows.

does that also mean ANY 1866Mhz module RAM will be compatible with my motherboard? as long as the module is Non-ECC and Un-Buffered

I am not going to say ANY module, because there is always some exception, but let's go with 99% should work. As for JEDEC, this is a global standard. To be in compliance with this standard, manufacturers have to follow its reference guidelines, so any 1866 should be PC3-14900.

I had 16GB of 1866 in my AMD FX build. It would not run higher than 1600. To attempt to do so caused an immediate crash and, yes, I ran Memtest+, swapped modules, tried other RAM, ran with only a single module, used a RAM cooler, tried the RAM in another motherboard (worked fine), ect.

As for fast RAM, I suggest you read this:
http://www.tomshardware.com/reviews/bulldozer-ddr3-overclocking,3209.html

 

[reyesz3]

The number PC3-XXXX is the peak transfer rate. What most people use is the data rate (e.g. 1600MT/s). The data rate is double the IO Bus clock rate and the peak transfer rate is eight times the data rate. This is all from the JEDEC standards: http://en.wikipedia.org/wiki/DDR3_SDRAM

1866*8= 14928 which is 14900. It should work on your board. If it doesn't, you machine probably won't boot, at which point you go in and try a lower frequency.

so basically according to JEDEC all 1866Mhz Modules should be PC3-14900? which is compatible with my motherboard as far as the Asus website shows.

does that also mean ANY 1866Mhz module RAM will be compatible with my motherboard? as long as the module is Non-ECC and Un-Buffered

I am not going to say ANY module, because there is always some exception, but let's go with 99% should work. As for JEDEC, this is a global standard. To be in compliance with this standard, manufacturers have to follow its reference guidelines, so any 1866 should be PC3-14900.

I had 16GB of 1866 in my AMD FX build. It would not run higher than 1600. To attempt to do so caused an immediate crash and, yes, I ran Memtest+, swapped modules, tried other RAM, ran with only a single module, used a RAM cooler, tried the RAM in another motherboard (worked fine), ect.

As for fast RAM, I suggest you read this:
http://www.tomshardware.com/reviews/bulldozer-ddr3-overclocking,3209.html

i have the AMD FX 6350, are you saying 1866mhz wont work ?!

 

[Tradesman1]

6350 is marginal, some will carry 1866 others won't, depends on the individual CPU and how much DRAM you want to run....

XMP is not strictly Intel mobos anymore, many of the better AMD mobos now employ XMP, either by itself or alongside the EOCP and DOCP (overclocking profile integration)

 

[reyesz3]

6350 is marginal, some will carry 1866 others won't, depends on the individual CPU and how much DRAM you want to run....

XMP is not strictly Intel mobos anymore, many of the better AMD mobos now employ XMP, either by itself or alongside the EOCP and DOCP (overclocking profile integration)

Thats just dissapointing...even if I manage to get the correct ram I cant be sure it'll even work -.-

Im planning to run 2 modules of 4gb to take advantage of the dual channel on the mobo.
I dont think my motherboard actually supports xmp I havent found anything of the sort in the booklet however all types of ram it suggested in the QVL support xmp .

 

[Tradesman1]

If not XMP, prob has DOCP or EOCP (OCing profiles) may still need to manually tweak, particualrly voltages....Good news is when AMD decided to tell the world the FX CPUs run 2 sticks at 1866 they were testing with 4GB sticks, so that improves the chances 😉 if you go 1866 (would suggest GSkill Snipers) and have a problem, give a shout or PM me, have done a lor with these setups

 

[reyesz3]

If not XMP, prob has DOCP or EOCP (OCing profiles) may still need to manually tweak, particualrly voltages....Good news is when AMD decided to tell the world the FX CPUs run 2 sticks at 1866 they were testing with 4GB sticks, so that improves the chances 😉 if you go 1866 (would suggest GSkill Snipers) and have a problem, give a shout or PM me, have done a lor with these setups

Will I actually need the profiles though? I was thinking of just manually OCing to 1866 if the modules are stuck on automatic settings of 1333 because of JEDEC

Funny you should mention that, I was just looking at the sniper series, the gun heatsink design caught my eye 😉
Thanks for that I will do

 

[Tradesman1]

Agree, I prefer manual, can normally tighten up and get a performance boost, if you have any problems, drop me a PM

T