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  1. Re:nice on Dual Channel Memory Shootout · · Score: 1
    So tell me, why do one company's ram perform better then anothers? or is it in the quality of the rest of the components as well?

    Off the top of my head, in order of impact on performance (and cost):
    • Speed rating of the chips (there aren't many manufacturers, but each has several different speeds available, and faster costs more, of course.) Often chips are made and tested until they fail, then "speed-binned," or grouped by max performance, and sold accordingly.
    • Printed circuit board (PCB) material and layer count. More expensive epoxy / resin materials (like FR4) allow tighter and more consistent trace etching, allowing tighter design rules and more efficient and matched routing. Number of layers and ground/VDD planes affect potential quality as well, and cost of course.
    • PCB design and trace routing. There's more to an SDRAM stick than just slapping on some chips. It's circuit design and, as such, there are better and worse designs. Moreover chip layout, trace width and length, placement and quality of passive components, etc. all affect performance. This is linked to PCB material above, since better material allows tighter design.
    • Quality control and testing. The best design in the world can be screwed up by process and you'll never know until you test. More expensive RAM OEMs test every part over a wide range of voltage and temperature using expensive machines. More testing ensures better parts (or at least a better understanding of how good each part it, and thus how it should be marked and sold) but costs lots of money in tester time.
    Hope that helps!
  2. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 1

    Thanks. And you are indeed correct sir. But the context of your comment puzzles me, seeing as how this article, the reviews and benchmarks, and every thread I've seen here refer to unregistered, unbuffered DDR SDRAM.

    I guess we should also point out that it doesn't apply to EDO, FastPAGE, VRAM, VirtualChannel RAM, SRAM, FLASH, or any others either. Just to be thorough, you know :)

  3. Re:Great tests, but lacking the new goodness on Dual Channel Memory Shootout · · Score: 1

    The ddr 500 you linked to has a cas latency of 3-4-4-8 not 2-2-2-2 so in effect it can pump 25% mor data at 1/2 the speed in cycles consumed.

    Do you know what the units of those numbers are (3-4-4-8 and 2-2-2-2)? Judging rom the rest of your post it seems you think they are time units, such as 3ns/4ns/4ns/8ns or something. That's not the case, though. The units are clock cycles. And a clock cycle at 500MHz is a shorter time interval than a clock cycle at 400MHz.

    You seem to miss that critical issue entirely, and base your conclusions on an unwarranted comparison of 400MHz clock cycles and 500MHz clock cycles (sorta like apples and oranges in this case.)

  4. Re:Results on Dual Channel Memory Shootout · · Score: 1

    Good choice. Probably the best DDR400 RAM out there (for low latency.)

    But, unlike some PC100 mobos that won't work with PC133, in the DDR SDRAM realm, it's always backward compatible (except for new DDR2, which is an all new interface protocol.) If your mobo/CPU works with DDR400, it will run the same (or slightly faster, assuming you're not at 2-2-2-2 with DDR400) with DDR500/533/550+

    Your good Corsair will probably do the tightest timing your mobo can support, but it's about $100 more than DDR500 that definitely will.

    Just FYI.

  5. Re:nice on Dual Channel Memory Shootout · · Score: 1

    Not sure why that would matter. Neither OCZ nor winbond actually make DRAM chips. In either case they're made by Samsung, Elpida, UMC, or one of the other (relatively few) companies that own the insanely expensive ($billions) chip fabs. OCZ, winbond, Micron, Crucial, Mushkin, Kingston, etc. merely buy the chips and make SDRAM modules out of them.

    It's not uncommon for one to buy spare stock from another (it usually benefits both -- the co. with the extra chips unloads excess stock and gets cash, the co. that buys them gets to fill outstanding orders and make important customers happy.)

    It's also not uncommon for the chip fabs to change markings on the parts after production, especiallly parts that are the same for many customers (contrast with ASICs, where this is unheard of.) We (I work for a semiconductor company that fabs chips, including DRAM) may make a million chips with custom marking for "foo company," then if Foo Co. cancels or reduces an order, we'll charge them a fee to cover the re-marking (usually) and recoup some money by selling them to another company.

    No harm no foul. If they changed the marked specs rather than the name, that might be interesting. This isn't.

  6. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 1

    Surely [more RAM modules is] potentially slower, not necessarily slower.

    No, it is necessarily slower. Maybe so small a speed difference that the available mobo RAM timing options aren't fine-grained enough to even tell the difference, but it will always take longer to propagate a signal from a driver to two loads (2 RAM modules), even if the modules are right on top of one another with no difference in trace length -- the second module adds to the input capacitance of the load seen by the driver, and all CMOS technology devices have delays that increase with load. If you add a buffer to split the signal, you indeed lower the load seen by the driver (one buffer), but then you add the propagation delay of that inserted buffer. Result: slower for a different reason.

    More specifically, you won't be able to push the timings as far with several sticks as you could with just one.

    Er, that's what I said. If you meant the reverse -- no.

    If it works with several sticks at at a particular set of timings then surely it will be equally as fast as with one stick with those same timings. Please correct me if I'm wrong, but that seems logical to me.

    Again, that's what I said. Right. I'm confused now -- you start off diagreeing, then repeat what you (seem to) disagree with as correct. AM I misunderstanding you?

  7. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 0

    No, I realize there are mobos with more than 2 controllers (though not very common), but you're right that I should have said "Dual" in my first sentence.

    However, if you scroll back up the thread and see the post that started all this, you'll note that the claim was "by separating out the memory into an array of smaller modules, you allow faster memory access." That is, for the same system (i.e., same number of memory controllers), this guy claims more modules will provide faster memory access.

    This, of course, is fasle, as has been established. Then someone else chimes in with the claim that memory access time "may not be slower, and may well be faster, if you have a multi-channel memory controller." Which is also false, as this poster (along with the original article itself) confuses latency (memory access timing) with bandwidth (total memory throughput.)

    To put this to rest, hopefully:

    More memory controllers or channels paired with one module each is the fastest for both latency and bandwidth. As you add memory controllers (assuming only one well-matched module each) you get more bandwidth with the same latency (with a few exceptions -- some mobos get slower with more modules regardless). As you add more modules to each controller, you get more latency, but still roughly the same bandwidth (just slightly less.)

    memory access time : memory bandwidth :: ping : network bandwidth

  8. Re:Haha on Can Your Car Get 1,700 MPG? · · Score: 1

    Exactly. They pay for the freeways and then pass the cost on to me.

    Er, right, so retailers have two prices -- one lower one for those who drive and pay their share of the "freeway tax," and one higher for you and others who don't. Sounds like it's more trouble than it's worth. I guess the ambulance has to charge you more too, since you don't want to normally pay for the roads that they'll use to drag you to the hospital. You'll have to pay to get into the free national or state park too, if you use the freeway to get there. And so on.

    Well, why should I pay for public schools?

    Because you benefit from having an educated populace?

    Especially if I don't agree with a lot of things that are taught in there, and I am planning on sending my kids to a private school.

    You still benefit from having some education and inculcation pounded into most people you have to live around.

    What if I don't want my earnings spent by a politician to pay for the education of people I don't even know.

    Then you'll pay more in the long run for the welfare it takes to feed the idiots, or failing that, for the police to protect you from them thieving and pillaging. Actually, since most thinking people aren't going to go along with your plan, you'll be on your own with a few other extremist Libertarians such as yourself, and so you can go live off the grid in the woods somewhere or something. Go for it!

    Why should my money be used to force people to stay in school that don't even want to be in school?

    Because they need it, whether or not they realize it or not yet as youths, and we've all sort of agreed to try to give it to them and not let kids make decisions they're not prepared to make intelligently. There's a lot wrong with the system (teacher's unions, stupid curriculae, wasted money, too much administration, etc.) but your solution is too extreme.

  9. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 2, Insightful

    I'm cool (and home) thanks. But somehow I just got +5 for telling a guy that he has "no fucking idea what he's talking about." Twice.

    It was true, of course, but it's still kinda funny.

  10. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 1

    ehowa==funny

    ehowa!=fnord

    But now I have to kill you :)

  11. Re:nice on Dual Channel Memory Shootout · · Score: 1

    Thanks for replying. Not much there (silly allegation that OCA re-brands memory chips, which all SDRAM OEMs do,) but it is something, which I said it wouldn't be.

    I take back my smart-ass vitriol :)

  12. Re:I was going to mod you up.... on Dual Channel Memory Shootout · · Score: 1, Funny

    Keep the karma points; I don't need them. This just happens to be a subject I researched in detail recently and, instead of finding a great, in-depth, up-to-date review here on /. that would make me say "why didn't I read this before buying," I get this old article, with insanely misinformed posts that make me wonder why I bother with tech articles here.

    But you're kinda right. I brought home chocolate mousse cake from Appetito and ate it a little while ago. It rocked, but was heavily sugary. And my wife fell asleep before I noticed, so no nookie tonight. I'll be OK -- thanks for caring though :)

  13. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 2, Informative

    Maybe, but that'd be missing the point entirely, since this article is about RAM access timing -- comparing different RAM brands and types in the same system.

    Everyone who is paying attention (or thinks for a second) knows that adding memory controllers to the CPU can increase memory bandwidth (it's 2 pipes instead of 1, after all), and this increase is more than the gain found in overclocking your FSB (front-side bus, or memory controller) from 200MHz to 210MHz or going from 3-3-7-11 access timing to 2-2-2-2.

    This article is all about how fast you can run your FSB and how tight you can set the timings for various brands of RAM. Not how much more memory bandwidth your system can get by adding memory controllers/channels. That's a CPU upgrade, not a RAM swap. Wrong topic.

  14. Re:Great tests, but lacking the new goodness on Dual Channel Memory Shootout · · Score: 1

    You got lucky.

    Maybe, but DDR500-qualified RAM is guaranteed to achieve better poorest timing (worst-case, of the worst sample of all batches) than DDR400, which was the fastest reviewed in the article. My point is that, given even DDR550 is available, they seem to have completely missed the "sweet spot." For the same price as their best DDR400, you can have DDR500 that will either (1) run at 250FSB if you have or are overclocking to that or (2) give better timing (closer to 2-2-2-2) in DDR200/333/400 systems.

    Sometimes low-latency memory doesn't even work at lower than rated speed with more than one module installed if you don't buy matched, pretested pairs.

    Yep, that's why you make sure the worst case performace specs meet your needs and are the best value for the buck. You can't predict how your part will fall in the min-max distribution of the batch in question, and returning RAM because you can't OC it to the level you want is dickish, so you have to pick something that is guaranteed to do what you want.

  15. Aargh, again with the confusion. on Oxford Students Hack University Network · · Score: 4, Interesting

    An IT Officer at College A said: "Short of keeping the network as segmented as possible, there is very little we can do." In a warning to students, he added: "I am able to monitor my network, and student regulations mean that any member abusing it would find themselves before the Dean."

    Er, require strong passwords? Hm, yeah, that'd work, and I guess it is "little" to do :)

    The OxStu has agreed not to pass on the methods used to carry out such actions, which fall foul of both the law and OUCS guidelines. One computer expert told The OxStu that the actions were virtually untraceable.


    How clever of them -- security by obscurity. I'm sure those "methods" would be far too complex for us to understand anyway, right? ;)

    It can take less than a minute to obtain an individual student's email password. A student at College B whose password was compromised told The OxStu: "It's absolutely ridiculous that security could be so light. I'll certainly be changing my password regularly in the future."


    Oh! So that's it. Weak passwords (or maybe a little social engineering, or both.) Gosh -- better keep a lid on that secret.

  16. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 3, Informative

    It may not be slower, and may well be faster, if you have a multi-channel memory controller. YMMV. BMSMA.

    No, multiple modules will never be faster -- a mulit-channel controller will be the same with one or two modules; slower with more than two (which is possible.)

    More modules is never faster from a memory access timing standpoint which is, again, what this discussion is (or should be) all about. You can, of course, increase overall system memory bandwidth by adding one each memory controller and SDRAM module, but that's irrelevant here (even in that case, you'd want faster RAM so that the CAS, RAS, and other latencies can be minimized and bandwidth increased a bit more.)

  17. Re:TrustedReviews? on Dual Channel Memory Shootout · · Score: 1

    I don't get it. Why Japan?

  18. Re:Results on Dual Channel Memory Shootout · · Score: 4, Informative

    Super! But note that the article is old, or at least a bit behind the times (it takes time to compile, plot, and publish all that data!) Newer, faster RAM is already available and can allow even tighter RAM timing (2-2-2-2 anyone?) and more overclocking (my DDR500 runs stably at 325MHz FSB.)

    For example, you can get PC4000 (DDR500) @ $259/GB, PC4200 (DDR533) @ $283/GB, PC4400 (DDR550) @ $314/GB, PC2-4300 (DDR2-533, if you happen to have a DDR2 mobo, the others above will all waor in any DDR mobo) are all available cheaper/MB than the high-performers reviewed.

    What'd you pay for that "fastest PC3200 memory on the planet" and let me know how fast you can push it (and be stable) once you get it?

  19. Re:Mushkin? on Dual Channel Memory Shootout · · Score: 1

    They asked vendors for (presumably free) samples from for the tests. My guess is Mushkin declined to waste money on the free samples -- they don't need to. People who buy Mushkin know why.

  20. Re:nice on Dual Channel Memory Shootout · · Score: 1

    So, are you going to tell us from whence cometh this "understanding" or, by your silence, will you implicitly admit that you made that up, or heard it from a friend-of-a-friend, and actually have no fucking clue?

    Your move! ;)

  21. Re:RAM Speed Differences on Dual Channel Memory Shootout · · Score: 4, Informative

    Why do people make wrong claims in such a matter-of-fact manner? Is it ignorance or malice?

    Whatever, more modules in general leads to slower access time. More sticks (modules) of RAM adds to the capacitance driven by the memory controller, and therefore increases the propagation delay on those traces. The more connected modules the longer total trace length driven by each IO buffer of the memeory controller. The difference is probably negligible for all but the edgiest overclocker, but there's always a speed advantage for fewer modules.

    I did a quick google and found this example to back me up, but it's not really needed as you clearly have no fucking idea what you're talking about and could not cite one single reputable argument to back up your insane claim. One of your friends spewed that nonsense and you're parroting it because it sounded reasonable. Of course, that's only because you have no fucking idea what you're talking about.

  22. Re:Results on Dual Channel Memory Shootout · · Score: 2, Funny
  23. Re:Dead after 3 on Dual Channel Memory Shootout · · Score: -1, Offtopic

    It's fine, dumbass. Check your network connection.

  24. Re:how convenient on Dual Channel Memory Shootout · · Score: 1

    They also put it into one page so that, er, well. I dunno why.

  25. Re:33 pages on Dual Channel Memory Shootout · · Score: -1, Redundant

    That's already been covered by someone with enough couth to post as AC. Before you even.

    You redundant whore.

    :)