what do you need to look for when adding RAM?

[hoofhearted4]

i know that if possible, you should get the exact same RAM, but if thats not possible, what do you need to look for if you wanna Add RAM?

 

so what if i added similar RAM and im talking extremely similar. both 8gb. both ddr3 1333. both 9-9-9-24. both 1.5v. both GSkill Ripjaw X, the only difference is there model numbers are off by one letter (XXXXXD vs XXXXXS)

 

what if i wanted to mix two different RAM? for example a GSkill Ripjaw with a GSkill Sniper? if they were both 1333, 1.5v, 9-9-9-24, i mean what else is there? im not saying i would, but yea, not just for me, but for anyone who would want to know, what else would you need to consider.

 

just curious lol.

[SineWaveDrox]

I don't claim to be an expert in this area (or in any for that matter), but I will explain what I know on this topic, gathered from what I have read in posts by GSkill employees.

 

While it is possible for RAM to work together when purchased separately, the chances of that working are far less than purchasing a kit that includes the full amount. An example of this would be getting two 8GB kits in the configuration of 2x4GB each being compared to a 16GB kit composed of 4x4GB. In the case of the 16GB kit, the full set of RAM is tested to make sure that the entire kit will work together at the specified speeds, timings, latencies, etc. Each of the 8GB kits would also pass those tests, but separately. There would be no guarantee that the two kits, when combined, would be capable of functioning at the advertised specifications.

 

Long story short, two different sets may work together, but there is no guarantee. As for the two sets being different model numbers, I would imagine that would only make compatibility and functionality less likely.

 

Again, this is not expert testimonial, I am simply stating what I remember reading in posts from GSkill employees. I could be misunderstanding what they wrote, so anyone with greater knowledge than I, please feel free to correct me.

[M48A5]

Not being very tech savvy, I would like to relate my experience with adding RAM. I just recently doubled my ram by buying the sticks that matched specifications with what was originally installed in the computer. The additional sticks were not by the same manufacturer and because of budget restraints, they were not added at the same time. I have had no problems. So, in my experience, matching the specifications was all that was required.

[Thor.]

It has to be the same make and model for it work work properly, mixing ram is just as bad as mixing a sli card with a crossfire card. My advice would be to stick with a bundle.

It can cause timing issues.

Edited April 18, 2012 by Thor.

[FMod]

While it is possible for RAM to work together when purchased separately, the chances of that working are far less than purchasing a kit that includes the full amount.

In practice, there's no difference unless:

a) They are different models

b) We are talking about exceptionally high clock rates, like DDR3-2533 and above.

 

In the case of the 16GB kit, the full set of RAM is tested to make sure that the entire kit will work together at the specified speeds, timings, latencies, etc.

More than 99% of memory kits are actually never tested at all.

 

That is, no one installs them in a motherboard with a CPU, to try and boot up, run some tests, etc. That is manual labor and a lot of employee time. Memory modules are tested without installation, using a series of standardized electrical tests. It is impossible to test them in combination this way.

In addition to this, makers do install and properly test some modules, especially if they advertise high clock rates. It may range from 1 out of 10,000s for mainstream to something like 1 out of 100 for high-end lines.

 

This may differ for exceptional clock rate kits, where the chance of random modules working at that frequency is too small to do batch-testing. Even so, if you look around overclocking boards, you'll hear a lot of customers complaining that the DDR3-2133 kit they bought doesn't actually work at 2133 at stock voltages; these clock rates are normally not guaranteed. For even higher clock rates, it's fairly common to be unable to get the advertised rate, as it is to go above.

 

Mix-and-matching RAM used to be troublesome with early SDRAM and DDR, but starting from DDR2, it's very rare to hear of any trouble. Even completely egregious combinations, like 2GB+512+512+1GB all from different makes and different years, with 2G+512 in black and 1G+512 in blue slots, tend to work.

However you might not get higher clock rates than standard DDR3-1333. Also, it's common to be unable to get full speed with all 4 slots filled, even if all four modules came as a kit.

 

 

 

so what if i added similar RAM and im talking extremely similar. both 8gb. both ddr3 1333. both 9-9-9-24. both 1.5v. both GSkill Ripjaw X

Why would you be paying extra for the brand and the looks when buying bog-standard DDR3-1333?

Anyway, at 1333, there should be no problem at all.

[blove]

Not sure if you know, but D is for two sticks and S is for one stick when it comes to G.SKILL part numbers.

[hoofhearted4]

so what if i added similar RAM and im talking extremely similar. both 8gb. both ddr3 1333. both 9-9-9-24. both 1.5v. both GSkill Ripjaw X

Why would you be paying extra for the brand and the looks when buying bog-standard DDR3-1333?

Anyway, at 1333, there should be no problem at all.

 

to make a long story short, i already have 8gb of that specific RAM here. i dont however have a computer. bought the RAM before i bought my computer, then ended up not buying a PC. should be able to build one this summer if all goes according to plan (which it didnt last summer lol) and i was thinking with RAM so cheap i might just throw in 16GB total for poops and giggles. i really could care less about the looks cause i am not going to have a side panel window. thats just the RAM i already have

[nosisab]

They work under the specification alike, what would be a problem is one stick could overclock nicely while the other could become unstable compromising the whole.

 

The bottom line is: if the pair works stable under the same specification they work...

 

PS: all those timing numbers are to grant the states are already steady and stabilized when the memory is to be read or written.

Edited April 18, 2012 by nosisab

[hoofhearted4]

i honestly dont plan on OCing my RAM. you get such little performance out of the increase unlike a CPU or GPU, that OCing RAM means almost nothing. not worth the hassle.

[Thor.]

Hmm i have 8gb of patriot ram at 1866mhz, you do notice a difference when it comes to stability and OS performance :thumbsup: Better latency.. Edited April 19, 2012 by Thor.