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Is Rambus Destined to Return?
An anonymous reader pointed us to an article running over at Tom's that talks
about the world
of ram and criticizes the performance of DDR. The article goes
into DDR333, DDR400, and Rambus, and explains the issues at higher
clockspeeds.
Intel had 2 reasons to bring out SDRAM based boxes:
1) Cost. Most consumers and business desktops don't care about speed, and RDRAM costs too much extra.
2) Speed. RDRAM looked fast because it was implemented with multiple banks. You can do the same thing with SDRAM, if you like. And that would give an apples to apples comparison.
on what systems you are working with? if you want a performance p4 system then obviously you use rambus... and if you want an amd system you use ddr(since there is no rambus/athlon chipset)
and until there is a rambus/athlon chipset i don't really think we can gague the real world implication of it...
either way i have better things to do with a few $100 than put it into a more expensive chipset/cpu/memory rig. if you have the extra money and the rambus system gives you what you want, then more power to you. overall, right now, you can't say either system is "the best" in ever possible catagory
I believe sex is highly over rated... unless it involves me
While Rambus memory might not be the best design in the world your arguments for why it is garbage are retarded. The memory is interleved and runs hot. There's nothing wrong with interleved memory designs except the fact you have to buy two modules rather than one. If you use memory from different manufacturers in SDRAM based systems you can wind up with a system not booting too. It depends on how robust your memory controller is. They run hot but have twice the memory bandwidth of PC2100 memory. That sort of tradeoff is always inherent in a computer. You could say RDRAM is garbage because of the limited number of suppliers or patent issues or memory even the high latency. Instead you picked the fact it was interleaved and hot.
I'm a loner Dottie, a Rebel.
Speed. RDRAM looked fast because it was implemented with multiple banks. You can do the same thing with SDRAM, if you like. And that would give an apples to apples comparison.
The whole advantage of RDRAM is high bandwidth/pin, and the fastest RDRAM has more than double bandwith/pin than the fastest DDR. RDRAM is very cheap to make dual channel because it has fewer pins. It is very expensive to make a dual channel DDR system because it requires that many more signals. The only dual channel DDR system I know of is the upcoming Serverworks Grand Champion chipset for the P4 Xeon which is very high-end (and no doubt expensive).
How is the parent post +4?
He links to an obsolete article from Q3 2000 about RDRAM on the Pentium III...
He talks about the "insanely high latency", and it's pretty obvious he's exaggerating slightly.
RDRAM's latency, particularly with the upcoming PC1066, is far better than people give it credit for. See this AcesHardware article.
PC1066 RDRAM latency for 128 bytes: 207 cycles
PC800 RDRAM latency for 128 bytes: 247 cycles
PC133 SDRAM latency for 128 bytes: 229 cycles
Slashdot moderators: Would it kill you to check the links before going points-crazy?
Were the AMD systems Duron-based? :)
:)
What about games that -don't- love the P4, like, say, -any other game- (even those based on the Q3 engine)?
But no one needs to do the same testing you did. They can just look at all the tech sites. Hey, you already visited Tom's Hardware to read this article, check out who -he- thinks has the "best possible performance in 3D".
At one time, your "best possible performance in 3D gameing" applied... That time was the year 2000, and Q3A was the most demanding benchmark anyone could cook up It is now 2002, and the world has moved on from Q3A, and P4 lost that crown. But nice try.
You should have said "media encoding", because then you'd have been right even today.
As to AMD using Rambus... It'd suck. P4 does better with RDRAM than DDR because it's a highly pipelined, high-clocked machine that craves bandwidth. The K7 is a very wide machine, and for it the worst thing that can happen is having to stall waiting for data. The latency of RDRAM would kill the K7. You'll note that the dual-channel nforce (higher theoretical bandwidth than the i850, and 2x the KT266A) doesn't outperform VIA's chipset. An likely reason would be that the KT266A has lower latency, and that more than makes up for the extra bandwidth (which K7 doesn't need).
The enemies of Democracy are
Then the political aspect is ignored and he talks almost exclusively about technical issues about why Rambus might theoretically be better, and uses existing intel chipsets as evidence.
Hello? Answer the question, please? Has Intel ever come out with a non-crippled DDR chipset for the P4? How do Intel's DDR P4 chipsets compare to non-intel DDR P4 chipsets? (ARE there any non-intel P4 chipsets?)
How much of the problem is political, and how much of it is a real technical issue?
-- ;-)
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Um... How was that FUD?
It's true. If the heatsink falls off your Athlon it is toast. (note that just in the last week or so a board was released that supported the XP's thermal diode... but for all other boards/chips, you still get toast)
Tom isn't the genius a lot of people think he is (or that he'd want you to think), but that was not FUD.
The enemies of Democracy are
First, it looks to me like RDRAM is still about double the cost of SDRAM, according to Tom's Hardware's own price guide.
They have $93 for 512mb SDRAM and $175-250 for 512mb RDRAM.
My question is this: Let's say I have a choice between 512mb of SDRAM and 256mb of RDRAM. Would the SDRAM not almost always be faster because RAM, however slow, trumps swap space every time?
In other words, isn't the amount of memory I have more important than how fast it is?
Many moons ago, I had a SGI O2 workstation. Tremendous memory bandwidth, but memory that cost 10x more than anything else. As a result, it could be embarassed by lesser machines, since I couldn't afford to load it up with RAM.
I see Intel repeating the same mistake when it decided to focus on RDRAM.
Apple is putting L3 cache in their G4s so that the use of expensive RAM is confined to a relatively small and affordable amount. I can upgrade my PC133-equipped G4/450 dual processor to the latest 1ghz dual processor, put my 1.5gb RAM in it, and fly. That seems like a good compromise to me, maybe better than going to DDR, which I would have to buy new.
Thoughts?
D
Historically RDRAM has been plagued by cost, which has deterred its adoption, but this isn't why average reader of Slashdot dislikes it. They might claim that they think it's technically inferior (PC600 and PC800 have more latency than SDRAM, but PC1066 and PC1200 RDRAM will likely be out within the next year), I think a large majority of hatred of RDRAM comes from Intel and Rambus's business practicates.
Intel and Rambus were hoping to strangle the market into adopting RDRAM in order to hurt Intel's competitors, and when this failed (RDRAM's prices lead people to adopt PC133 and then DDR), they attempted to obtain royalties or sue developers of alternative memory technologies for patent infringement of one form or another.