Slashdot Mirror
PC1066 RDRAM vs. DDR SDRAM
Brad wrote into send us his "Comparison of PC1066 RDRAM vs DDR SDRAM. Quote - RDRAM is considerably more expensive that DDR SDRAM, and up until now the 100MHz PC800 specification didn't do well in comparison. Just recently 133MHz PC1066 was launched, and is now officially supported by the new Intel P4 and the Intel 850E core logic chipset, but this time promises to bring memory performance to the next level."
Why name memory chip standard after the year in which the Battle of Hastings was fought?
http://www.theinquirer.net/24050203.htm
That said, PC1066 has been tested before (can't find the article at Ace's Hardware), and the bandwidth of DRDRAM appears to compensate quite nicely for the P4's generally lousy architecture, as does its increased cache size (now 512k L2).
I wonder how expensive a graphics card with RDRAM would be, or if it would be any faster?
"I don't know that atheists should be considered citizens, nor should they be considered patriots." - George Bush
Why didn't they show us any Quake III comparison benches? We all know that at lower resolutions the processor drives Quake III and that its extremely sensitive to memory bandwith capabilities. Anyway it appears that RDRAM 1066 is a definite improvement over RDRAM 800. Its good to see that Intel is still continually raising the bar.
Also I believe there were some initial benches (better ones) on http://www.tomshardware.com
J
I love idealists not because I am one, but because they make life bearable for pragmatists such as myself.
The right way around would be to report that there now are PC1066 RAM available that supports the I850E platform.
Apparently the chipset is just an overclocked variant of the earlier variant and could not use the slowest version of the PC1066 standard memory. Ironically the only version available when 850E was launched.
www.theinquirer.net, wish they had a better back-catalogue
fine, this is all well and good, but how fast does it actually need to be before the gains are no longer better than the costs?
:D. (yes thats an exaggeration - y'get the idea!)
I'd presume when it all as a whole stops memory technology as a whole from progressing. At the moment a 'considerably more expensive' RDRAM setup may only give slight performance gains (which is a pity for people who buy it expecting more) but the less we rely on one single standard that becomes stretched as far as it can, the better. Future proofing in a way, perhaps. Suddenly next year we could be facing an incredible advance in cpu speed which absolutely requires speed at costs that are now prohibitive to work at its best.
Just who's going to need terahertz cpu's with terabyte/sec bandwidth... is another question
a grrl & her server
What a bogus comparison.
PC2100 is old news, and 1066 RDRAM is just being released.
The proper comparison would have been against PC3200, or PC2700 at least.
N.B., I've been using PC2700 in my machine for two months. PC3200 is about 33% more expensive.
--Blair
While the benchmarks he ran show nice bandwidth figures (Negligible, really, in light of how expensive that RDRAM is- if that's all this new memory spec can do, well...) it doesn't tell the whole story. There's bandwidth and then there's latency. In the case of RAMBUS, there's more latency involved with the access of the memory than with DDR SDRAM- latency that may eat some or all the bandwidth gains you see there when you start doing something other than benchmarks. If it's not really much faster (Sorry, it's not when you start looking at the bigger picture), why are you spending 3 or more times for it?
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
Of all the tests done between these two, about a 5% improve was the most that the PC1066 had. How exactly does about a 5% improve justify the (previously true, now perhaps perceived) significant increase in price?
It ALMOST sounds like someone *COUGHRDRAMMAKERSCOUGH* was "supporting" the writer of that article, their adjectives were too strong for the data.
-Jeremiah
There's bandwidth and then there's latency. In the case of RAMBUS, there's more latency involved with the access of the memory than with DDR SDRAM- latency that may eat some or all the bandwidth gains you see there when you start doing something other than benchmarks.
Aye, I can see where that would certainly limit things for general-purpose computing, where one device is needed to do a bit of everything - but perhaps some situations, where constant linear access of RAM is needed may benefit from DDR. Today anyway...
I don't know - I'm not quite that into the tech, more throwing around ideas. I do tend to go with the idea that everything is somewhat useful in its' own way, and has the possibility to lead to the incredible. It's a bit pollyanna, but this is slashdot and there's enough negative to balance out *grin*
a grrl & her server
I think I'll wait until The guy who wrote this hardware report writes on this issue.
1) RDRAM doesn't die because Intel still supports it.
1a) Intel still supports RDRAM because it wasn't a 100% bad decision, and they invested HUGE amounts of money.
2) Intel can't force stupid things onto consumers? How about an endless string of CPU upgrades based originally on the 4004? Motorola dumped the 6800-based line for the PPC, which is what Intel has been too scared to do. If IBM hadn't fallen on their fat and lazy ass, the PPC probably would have cut Intel's market share to about 40% right now. (and we'd have a better windows CPU than the P4)
"People who do stupid things with hazardous materials often die." -- Jim Davidson on alt.folklore.urban
I still don't get what the deal is with all this Mhz....
Why can't they just do interleaving (call it stripping/RAID-0 for memory)? No need to crank up those Mhz's, but spread the load over a couple of DIMM's. Most large systems (at least Sun I know off) still use 100Mhz or so DIMM's but do 8-way interleaving (maybe even higher) to get their high memory bandwidths.
The market seems to be demanding higher Mhz's and seems to forget there's other stuff involved. Just look at IBM's Power4, Sun's UltraSparcIII etc... Lower Mhz's (or Ghz's) but with a big level-2 cache and by using SMP they're able to beat whatever Intel/AMD system you put them up against.
Basically, CPU cooling has been hitting us for a good while.
From an article about a bigass Beowulf cluster running Transmeta processors, you have Wu-chun Feng of the Los Alamos Labs stating
Oh my. So - what else can we do to stop this trend? Relatively slow multi-processor machines. If we keep working on multi-threading our applications, we might be able to make a computer with 8 1ghz efficient chips outperform an 8ghz Moore-compatible Intel hype-chip-based system. Really. Multi-processor machines have traditionally been too expensive for the desktop. The software people have not spent a lot of time making sure that the regular end-user applications scale well across several processors.Take something like a web browser. Given a bit of wizardry (obviously, we need to consider concurrency and critical sections), you could have separate images downloaded and processed by separate processors. Your flash ad would run on another processor.
Frankly, I'm wondering what's stopping us from using this approach to increasing performance? Is this like the fact that OEMs equip the low-end PCs with too little RAM so that Joe Shmoe will buy a new one as quickly as possible, since he does not know that spending 100 bucks on more RAM will make his computer last another year or two?
And, really, as long as the focus is on the gigahertz, do the chip makers really concentrate on making their designs as efficient as possible?
Stop the brainwash
I talked about the architecture of the Pentium IV with two of the architects. (In Portland, Oregon, it is sometimes possible to meet them at parties, and we have become friendly.) In perhaps 18 months, the speed of the P4 will reach 6 GHz. That's when you will be seeing more of the benefits of the design.
Remember the 1 GHz P4? That was a marketing push to try to counter AMD's competition, not something the engineers wanted. In many ways, it made the P4 look bad, because the P4 was not designed to run at 1 GHz. People still remember the poor 1 GHz benchmarks; those benchmarks have done lasting damage.
In my opinion, Intel's marketing is not technically skilled, and not skilled overall. (One of the engineers strongly agrees with this.) One of the tasks of the marketing people now should be showing people how the much faster processing speed can be used. Intel marketing, having little technical knowledge, cannot possibly do the job.
Also, Intel's management has foundered since Andy Grove got tired of running the company. The problem with poor management pre-dated his cancer. No matter what you do, if you do it for too long, it stops being exciting and becomes boring, and it becomes difficult to give it proper attention.
The article is about PC1066, a new kind of memory. The memory specific benchmarks do show quite a big performance increase!! (see the last three graphs on this page of the article)
The fact that the other graphs show little or no performance difference I think is quite likely due to the fact that the tests employed have different kinds of bottlenecks due to system limitations -- limitations other than memory bandwidth.
You might get similar results if you tested a new sound card (for example) that had faster hardware acceleration -- sure, the Quake III benchmark would only show a small difference, but another test that made more significant usage of the sound card (a test in Cubase for example) would show a greater performance increase. (Umm, I know it's not a great example, but I'm hope you get what I mean!).
VIA chipsets do suck, so don't use one.
Nvidia's Nforce is looking good and solid, I haven't heard a single horror story about it infact.
SiS 735/745 lines are nice, cheap, pretty fast, and they work.
It's completely possible to build a fast athlon system without even having to look at a VIA chipset. so please, stop using VIA as an excuse to bash AMD.
If intel is still supporting Rdram so strongly, how come there isn't an Rdram supporting chipset on intels future roadmap?
What does "the next level" mean? Does that mean that mean that my fifth level fighter will have 35,001 experience points with the new technology? Does it mean my cube will be moved upstairs? Does it mean the little bubble will sit in the middle of the glass?
That phrase should ring Dilbert-esque alarm bells. If there were awards for the most over-used marketing phrases, "the next level" would be due to win the grand prize this year.
Did you know that there are about 788,000 hits on Google for that phrase?
I'm sorry, but I have a bit of trouble taking any article seriously that uses that sort of marketing-speak.
Is there not? Excellent! That might mean that Intel will continue to support it on the P4 line, and then let it die a miserable death.
They can't dump it yet, because most of the early P4 systems were sold to companies who want some ROI before the hardware dies. If Intel pulled the plug 100% right now, Sun would reap the benefits.
"People who do stupid things with hazardous materials often die." -- Jim Davidson on alt.folklore.urban
Having not been in the market for new hardware for the past 2 years, would someone be kind enough to explain the differences between the different kinds of RAM mentioned in all the replies? PC2100, PC3200, DDRxx, etc.? Just a quick primer would be great. Thanks.
Vote monkeys into Congress. They are cheaper and more trustworthy.
i850E is the last Rdram chipset on Intel's roadmap, and that is already here.
hell, their new server chipset (the E7500) is DDR based.
They used the very latest RDRAM, but they used year-old, PC2100 DDR SDRAM. Hmm, I wonder who will win this battle!
PC2400, PC2700, and PC3200 DDR SDRAM is out there. Why didn't they test against that?
- A.P.
"Remember when the U.S. had a drug problem, and then we declared a War On Drugs, and now you can't buy drugs anymore?"
Take something like a web browser. Given a bit of wizardry (obviously, we need to consider concurrency and critical sections), you could have separate images downloaded and processed by separate processors. Your flash ad would run on another processor.
Web tasks tend not to be processor-bound. You're limited by your 'net connection for these (you can draw an image far faster than you can download it).
It turns out that most of the tasks people do either aren't strong loads on the system at all (e.g. surfing, email, word-processing, spreadsheets) or are limited by some other part of the system (memory bandwidth, disk, or graphics card).
Of the remaining tasks, most aren't easily parallelized (or at least not automatically). Of the ones that are partly parallelizable, the serial part of the task tends to cause bottlenecking, which gives you rapidly-diminishing returns (look up "Amdahl's Law" for a deeper explanation of this).
The only processor-intensive, easily-parallelizable task that's currently done is 3D gaming, and the processing load for that is mainly handled by the video card, not the CPU. Graphics cards already parallelize to some degree on-die, but can't have more than one graphics chip without driving up the price of the card considerably. While this can be (and is) done for high-end cards, consumers prefer cards that are at a sane price.
In short, in the one place where most people would benefit from a multi-chip solution, you won't see it.
Frankly, I'm wondering what's stopping us from using this approach to increasing performance? Is this like the fact that OEMs equip the low-end PCs with too little RAM so that Joe Shmoe will buy a new one as quickly as possible, since he does not know that spending 100 bucks on more RAM will make his computer last another year or two?
Actually, it's that Joe Schmoe *prefers* to buy as cheap a computer as he can get his hands on. This is why you don't see many machines sold with a vast amount of RAM, and why you don't see many dual-processor machines sold.
People apparently really _do_ just want cheap machines, not optimized machines.
And, really, as long as the focus is on the gigahertz, do the chip makers really concentrate on making their designs as efficient as possible?
Yes - if you mean performance-efficient. Being able to say that you kick your competitor's ass in benchmarking does make some difference (especially if games are some of those benchmarks).
There isn't much incentive to be power-efficient beyond the amount needed to keep your chip from melting into slag, for desktops, at least. There are many low-power offerings already used in palmtops and embedded devices.
Power efficiency _is_ an issue, as reasonable power dissipation is the primary limit to a computer's clock rate. However, as long as people are willing to use computers with fans and heatsinks, your desktop processor will dissipate 50W+.
actually, the Nforce boards are right on the heels of the KT266A/KT333 boards, anyone who's willing to forgo stability for the extra 1-2% performance they'd get from a KT266A/KT333 board is an idiot, it's that simple.
the SiS735 lags behind, but not so much that you'd notice it if you weren't running benchmark suites all day, or throwing heavy duty tasks at it which would probably be better served by an AMD 762 based board and a pair of Athlon's.
FYI, I'm using an SiS735 right now, it works. it's fairly fast, it was cheap. OTOH I have a complaints list the length of my arm about the Asus VIA Apollo Pro 133A board that sits in the P3 next to me.
the problem is, people have the same attitude that you do "If they were better people would be using them" and so nobody actually bothers to try them to discover than AMD without VIA is a perfectly workable solution. catch-22 and all that.
Thank you Jar Jar, good question, for the hardcore EE peeps, here's some PDFs so disable ROT13
DDR 133 timing sheet
Rambus timing sheet
A caveman dreams of being us, the incalculable power and riches. We dream of being Q, then what?
It appears so. I got my information confused: Intel confirms P4 speed revs. I confused the disappointing early P4 benchmarks and the problems with speeding up the PIII.
The overall point is correct, however. Intel's marketing created big problems for the company. Intel let events run the communication about the P4, rather than their own marketing explanation. For example, see Pentium 4 yields 'not impressive'. Someone leaked that story from a plant in Israel.
Now that I look at some of the old articles, I realize that Intel's marketing communication was even worse than I thought. In general, companies are having huge problems running highly technical operations with a large percentage of people who have little technical understanding.
My contacts at Intel insist that the biggest problems are with communication, not with fundamental details. To me, that seems right.
No, the P4 has an architecture that was designed for the computers of the future. It's like a small dog with very big paws. It will be impressive when it grows up.
The heat dissipation comes from using the P4 architecture with the larger design rules. As the die sizes shrink, the heat dissipation will go down, and the wisdom behind other elements of the design will become more apparent.
Notice that we are already seeing this effect. The 2.4 GHz P4 performs very well.
Intel is demonstrating a 5 GHz P4 that runs cool with no fan. See, for example, Intel to demo fanless, cool 5 GHz chip. Quote: "Intel has now formally released details of the 3MB cache on chip which it claims will deliver 1.5 to two times [the] performance over the current designs." [My emphasis.]
The utter sadness of Intel's marketing is demonstrated by the fact that this information is being brought to you by a guy [me] whose only connection with the information is that he sells computers to business customers and that he happens to live in the same city as Intel's design team. The guy happened to meet two Intel engineers at parties. If Intel had good marketing, you would already know these things.
The moral of the Intel marketing story is: Don't try to run a high-tech company with low-tech employees in marketing. If I were running Intel's marketing, your little brother and maybe even your mom would be asking you about Intel's great new achievements.
RDRAM 1066: 2.04 fps
RDRAM 800 2.03 fps
DDRRAM 2100 2.03 fps
DDRRAM 3200 2.05 fps.
Conclusion
I think we have a clear winner here. PC3200 DDR wipes the floor with the competition. Anyone who's invested in RDRAM is a loser, and knows it :). Too bad it took such a blatent lead in these upcoming Doom3 benchmarks in order to prove it.
Tune in next week to our program to find out how you really should say it.... Tom-ay-to, or Tom-ah-to.
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
I had a very nasty experience with 3 athlonXP motherboards. For this reason I threw the athlon in my bottom drawer in my closet and downgraded back to my pentiumIII 700 after several hundred dollars and over a month of time were blown.
:-)
Some of the problems are alot of athlon motherboards require apic irq sharing which linux doesn't fully support yet( read the article on soyo's mobo from last march here on slashdot), to requiring weird 400 watt power supplies, to incompatabilities with standard hardware like geforce video cards and even netgear nics( I had to buy an expensive intel etherpro, more info is available from abit's newsgroups) and even a few sound blaster lives, to also some freezes after several months of use from msi boards. Alot of you reading this have had nothing but great luck with there althons and I am not debating there are nice athlon machines out there but for now I am skeptical. For myself I will never buy a non intel machine again unless its a ti-powerbook
If you are on a budget and need something that is guarunteed to work then I would pick an intel box. There are more expensive and slower but you will not go through the hassle like I had. Oh and if you buy XP guess what? You will have to repurchase XP FOR EACH MOBO YOU REPLACE! This is what fucking killed me. I ended up buying Windows2000 professional to avoid this crap again. Yes, I need windows and linux along will not work for me. Intel boards are mostly extremely reliable. If its for school or work then you know that a downed system could really fuck you over and could cost you money and time. Alot of people had no problems with their athlons but I would advise you to pick safely unless your loaded. This is why people like myself buy intel based motherboards and chips. Stability and reliability are king for corporations and individuals.
http://saveie6.com/
Don't own any RDRAM (using an Athlon+DDR mostly) but the "RDRAM costs much more" argument is bogus. Compare what Samsung originals PC800 cost compared to brand name--not generic or House Brand--true CAS Latency 2.0 PC2100. It's a wash.
Quality PC2100 is frequently marketed as PC2400. On www.pricewatch.com, the difference between PC800 and PC2100 is $5 for 128MB.
I don't pick my platforms for the DRAM. I went with an AthlonXP 2100+ (1733MHz). But if I was going to buy a Pentium-4, I would use the i850E with PC1066.
---
See my earlier post, Several things discussed at the same time. (#3595451)
The initial points of the original post, "Evaluate the Pentium IV design at 6 GHz" were: 1) Don't worry, the P4 will get there, and 2) We shouldn't be reading about the P4 from "Hoser McMoose" or Futurepower. If Intel's marketing communications department were doing a good job, none of this thread would have been necessary. Not that we shouldn't listen to Hoser McMoose, just that Intel should do a better job of communicating. Because of Intel's poor communication, we are probably all getting it a little bit wrong.
However most good ideas come at unexpected times, pulling the memory (DDR or RDRAM or whatever) memory off the system bus and onto a dedicated bus straight to the CPU will make it a *lot* easier to overclock that individually and will relieve the FSB. It occured to me the L3 cache (on G4 and Alpha EV8) fits this criteria and operates on a seperate bus - the back side bus. I'm saying MOVE the whole system RAM to the backside bus. This would allow us to screw the FSB for most main memory requests.
You can keep a small amount of RAM on the FSB, this'll just be a DMA cache for HD and PCI device data transfers, etc. It sounds crazy enough to actually work.
The L3 cache will act as the main memory. The "DMA cache" and L1/L2 cache will write-through/write-back their data into this BSB main memory. Nice. I/O overclockers will work on the FSB, RAM bandwidth overclockers will work on the BSB. Overclockers' dream. Oops, I'm waking up now....
A caveman dreams of being us, the incalculable power and riches. We dream of being Q, then what?