Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I am looking into upgrading my custom built PC's RAM. I use the machine mostly for gaming, but I don't really know a ton about RAM, so I wanted to ask a few questions.

  1. The research I've done tells me there is a negligible increase in speed for anything above 1600 MHz. is this true or is it worth the extra money to go higher?
  2. Other than drawing more power from the PSU, is there any real difference in performance with different voltages (1.5V vs 1.65V)?
  3. most of the kits I've found in the 2x4 1600 range have a CAS latency of 9 and timing of 9-9-9-24. For a significant increase in price (usually about 1.5x), I can get either 8 or 7 and lower timing. Is it worth the cost?

What I am looking for here is someone to give a good explanation of what the different specs represent, and how that relates to the performance of the machine. Specifically, I'm looking for what specs I need to focus on for a good gaming rig. I am NOT looking for a "buy this, it's the best RAM" without an explanation of why. The information will be much more valuable as it will allow me to make my own informed decision.

As they say, give a man a fish, he'll eat for a day. teach a man to fish, and he'll eat for the rest of his life.

share|improve this question

closed as off topic by CharlieRB, Indrek, Dennis, 8088, Ƭᴇcʜιᴇ007 Oct 19 '12 at 3:26

Questions on Super User are expected to relate to computer software or computer hardware within the scope defined by the community. Consider editing the question or leaving comments for improvement if you believe the question can be reworded to fit within the scope. Read more about reopening questions here.If this question can be reworded to fit the rules in the help center, please edit the question.

    
wait. why was this closed? how is it off-topic? –  ewok Oct 23 '12 at 16:04

1 Answer 1

up vote 3 down vote accepted

Frequency is the transfer rate. The higher the frequency the faster the transfer rate. Higher frequencies require faster CPUs otherwise the frequency is wasted, waiting for the CPU.

Timing is latency. Each number in the Timing represents a number of clock cycles that it takes to get to an operation. CL-tRCD-tRP-tRAS-CMD.

  • CL - CAS latency. Time between the processor asking for something and the RAM returning it
  • tRCD - RAS to CAS. Time between the row/column activation in the memory matrix
  • tRP - RAS Precharge. Time it takes to lock and move on to new data in memory
  • tRAS - Active to Precharge Delay. How long memory waits until new access can be initiated
  • CMD - Time between memory activation and when a command can be sent to memory

Generally, lower is better.

I'm not really a hardware guy. My understanding of voltage is that I need to bump it up to maintain stability when I overclock my RAM (e.g. increase the frequency or kajigger the timings)

If someone says something is 'the best' they're being a fanboy or just plain wrong. The best is what you sit down and work out w/ respect to all components in your system.

share|improve this answer
    
Thanks, great answer. To make sure I have things right: 1) I have a 3.3 GHz processor, so any memory below 3300 MHz will improve the performance, and above that there is no point. 2) CAS is measured in number of clock cycles as determined by the RAM, so a CL of 9 on a 1600 MHz would be 5.625 ns. 3) voltage doesnt matter if I don't plan to overclock. if I do, I want higher voltage. Are these all correct? –  ewok Oct 18 '12 at 14:20
1  
@ewok current Intel processors can be damaged if memory voltage goes over 1.65v, so I would imagine that you want 1.5v memory to give yourself more headroom if you need to bump the RAM voltage while overclocking. This is just a guess though. Also, I've generally found it more worthwhile to invest money in other components instead of upgrading beyond 1600Mhz / CAS 9 memory. If you have unlimited funds, then sure, but otherwise you can get a much more noticable boost from a better Graphics card or harddrive (SSD?) or CPU (or more RAM, if you can benefit from it. 8GB is probably plenty though). –  Darth Android Oct 18 '12 at 14:25
    
@ewok I wish I could give you more of a specific answer regarding CPU and RAM settings but I drifted away from x86 Hardware when they started tossing out multiple cores and I got a job as an AIX Admin. I'm starting to get back in now as we move from Power 7 over to Linux/Intel. So 1.) I can't really tell you. 2.) That sounds about right, I believe 1333 freq ram with a CAS of 7 would be faster by about 200 Mhz because of the reduced overheard, however. 3.) Typically I only mess with voltage if I have stability issues. I wouldn't start by bumping up voltage, try without and see how it goes –  HayekSplosives Oct 18 '12 at 14:40

Not the answer you're looking for? Browse other questions tagged or ask your own question.