Guide to RAM

exellent addition to an already great post. kudos to WildStyle!!! :thumbup:

 

Thank you.

Royicus and myself decided it would be an idea to update it to cover RAM in general, in an attempt to counteract the increasing number of RAM threads where people do not understand what to buy for their particular needs, or are unsure on a number of points. We also got sick of people shopping by brand hence some of the comments in the article.

Royicus wrote the Buying Guide part, in blue, whilst I put together the rest. So, Kudos to him too.

 

Why thank you *tips hat*

Yep, I think it was time it was added. Now people can go out and buy good RAM that overclocks well, and may be cheaper than what they had in mind. I'm glad I finally typed that thing, it was always distracting me from my school work. When I was sitting in lecture, I was actually jotting down little ideas for the guide. Guess I'll have to read the book to figure out what the professor was saying

 

yeah, big Kudos to Royicus too. I never had in mind how much I was ignoring about RAMs until this post.

 

did'nt go through the entire thread...(just passing through )

need to ask something that i seriously need to know about...
does it matter if i have a single sided 2x1gb set on the Asus A8N SLI Deluxe
running on 400MHZ Dual Channel stock
VS
when compired to having a double sided 2x1gb running on 400MHZ Dual Channel stock

like how am i supposed to know if the ram i ordered is a double side or a single sided...
(do single sided DIMMs run in dual channel in the first place)

basically i want to get two 1gb sticks reason being just so that i can have them work @400MHZ stock in dual channel on my new AMD system

So what am i supposed to be looking for...any special specs for this to happen..
Some one said having 2 double sided sticks wont matter becasue it'll still not run @400Mhz even if i get 2 sticks...is this true?


should'nt one just order a set of Corsair or Kingstan 2x1gb expecting them to run dual channel on 400Mhz with out any problems..or is that not the case...

please i really do need to know..other wise im expected to screw my entire setup...

(remember im not talking about overclocking just standard DDR400 wroking on a standard SLI board /settings expected to be Dual Channel 400MHZ when putting two sticks of 2x1gb will it work )
i dont want it to be running at 333mhz thats exactly why im going for 1gb sticks...

its kinda confusing....

 

Alrighty...

You will only be forced to run 333MHz or 2T CMD when using 4xmodules w/ a current A64 core.
I think it's 4xdouble sided modules means 333MHz forced, and 4xsingle sided means 2T, either way it does not really matter since you are looking at 2x1GB sticks, you are not filling all four banks, and therefore shouldn't have any problems.

 

wish i could take you out for a drink..thanks...

so there's no need for me to worry about having 2x1gb
it will work @400MHZ dual channel without a hitch.on the AMD setup..


thanks...

EDIT while im at it..another question..
I've been told that 2gb of ram boggs systems down a bit..is that true..
and as far as i remember people always insisted on having more divided modules like 256+256 =512 instead of 512
or having 512+512 instead of 1gb sticks...for faster responsiveness..
so would the responsiveness of having 2x1gb sticks be lower then of 2x512 sticks

just a thought
By the way will there be an improvement in or for video editing programes along with games like DOOM3 on high resolution

 

People usually run 2x256 or 2x512 because a) the modules are cheaper (1GB modules are quite expensive to manufacture) and b) because they want to utilise the not-so-amazing feature that is Dual Channel. They of course need two sticks of RAM for that.
I don't see why having 2GB boggs down a system at all, though I also think 1GB is sufficient right now. If you have the money then usually it's the more the better though.
Video editing and such will benefit from more RAM yes, but the ability to play games at high resolutions is usually dependant on the video cards bandwidth and onboard memory size, rather than system RAM.

As for your RAM working fine, stick to a known brand. I know I always say do not shop by brand, but since ICs are not really an issue here, sticking to a known brand is a good way of helping to ensure compatibility.

 

you answered all my questions thanks for all your help...
thumbs up to this thread

 

Somebody tell me what that 2-2-2-5 means??

 

It's all in the second post, but I'll reiterate:

CAS-tRP-tRCD-tRAS
2-2-2-5

You can find out what each does by reading the article, but basically a lower number will result in higher performance from your memory. After all, if it takes fewer cycles to complete an operation, then it can fit more operations within x amount of time.

 

what are the things that would require a increase in voltage? i know a high fsb may require an increase in voltage to remain stable but will tightening the latencies also require a increase in vdimm to remain stable?

 

Yeah, it happens. It depends if the IC responds and if it has the potential to run lower latencies anyway.

An example could be OCZ VX (Winbond UTT.) At 2.6v it will only run 2-3-3-x, but w/ 3v+ you can run 2-2-2-x (how it's meant to be) and then see how the modules scale up with increased vdimm to hit the FSB/HTT you want.

 

i thought this would be a nice reference to add to this thread. it involves latencies and how it doesn't make a real world performance difference. [link]

 

Yeah, that's a good read. I'll add it.

 

one last question, will superPI detect unstable ram? i don't really trust memtest. it hasn't detected unstable ram before. i tried to get away with 2-2-2-6 timings and it passed memtest stable. i only found out my ram was unstable when i ran prime95 and it started to give me error.

 

SuperPI can detect general instability just like Prime, providing you run the longer tests, as most people only bench 1M and that test can often be passed on an unstable OC. Unstable meaning not Prime stable.
I would be suprised if SuperPI caught anything that memtest86 missed, and it's true that memtest does miss things, but IMO it's still always better to run it first before booting into Windows because I really don't want to boot into the OS w/ unstable FSB/Mem settings. Memtest personally not let me down yet.
I suppose if you want an all around test you should still use Prime. Even the tests that are not using a whole lot of RAM will pick up the instability given that you run it long enough (as you should anyway.)

 

When I am trying a new FSB/RAM OC, I usually do the following.

1st, I run memtest. I allow that to run a few times through. If it passes, I go into windows.

2nd, once in windows, I run 3dmark01.

3rd, if 3dmark passes, I prime for several hours.

I've had OC's pass memtest, and fail 3dmark. I personally use 3dmark before prime95 as 3dmark is a little quicker in detecting errors. Also, I ran an OC that seemed to have some stability in prime, but failed 3dmark. However, I only ran prime for i dunno, 20 min (which brings up that whole 3dmark is sometimes bit quicker thing).

So I just run those three, and if it passes all of them, I call it good.

 

I got a few additional basic questions about RAM...

First off, how do I check the detailed information about the RAM currently inside my system? I know its 512mb, but really nothing more than that.

Also, Can you mix different types of RAM? If so, what can mix and what has to be the same?

And lastly, what exactly does RAM do in the aspect of gaming? I heard from someone that normal RAM can also be used towards memory for rendering textures once your video RAM is full. Is that true?

 

For more detailed info on your RAM, you can take your RAM out and look at the S/N or product number that is on it. You can fire an e-mail to the manufacturer asking for the IC's on your RAM, and they will usually let you know.

Or you can google the IC's numbers and see if you can figure out what it is. That is what I usually do, and it has not let me down yet, except for stupid relabed OCZ Premier which OC's like utter crap anyway . . .

You can mix different kinds of RAM, like PC3200 with PC3200. Your RAM will run as fast as the slowest module. If you mix PC4000 with PC2700, your RAM will run at PC2700. You also need to make sure the timings and voltages are the same too. Usually, to make sure all this matches, people just tell you to get some matched sticks of RAM.

You can use RAM as textures in games, but it is slower than your video RAM. Commonly, it is called "AGP Aperture" in your BIOS settings.

edit: So, perhaps you aren't interested in the IC's that are used, but rather what the RAM itself is rated to run. You can use a program called CPU-Z to look up what frequency and timing you are currently running. If you want another stick of RAM, get another that can run those same frequencies.

Does that answer your question?