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AMD Going Dual-Core In 2005
gr8_phk writes "We recently learned of Intel's
plans to go dual-core in late 2005. Well it seems AMD has
decided to follow suit. It should be noted that the K8 architecture has had this designed in
from the start. Will this be socket 939 or should I try to hold out another year to buy?"
2's company, 3's a crowd, and 4 is for the fat cats who wipe their ass with 50 dollar bills.
you can find them all here. It seems news has gotten around, and that AMD's dual core will consume just about as much power as a single core CPU at 90nm.
ignorance is bliss. googlefiberatx.com
actually it'll probably be more like the processors gets so big that you just clip things onto the outside of it and it takes the place of the motherboard.
A feeling of having made the same mistake before: Deja Foobar
I have seen some licensing schemes that apply to per-processor costs... 1 CPU = $1,000, 2 CPU = $2,000 etc.
How long will it take to argue that consumers with a dual core processor should pay 2x the price? I'm betting not long.
Interestingly, in a review of P4 vs. K8, the K8 had a clear advantage at the 4 processor level and above, apparently because of reduced bus conflicts with their individual memory spaces. If AMD were to proliferate cores on chip, they'd wind up contesting for the memory bandwidth, just like the P4.
--- Bill
heat
Yes..the evil of all machines
the reason why when the AC is not on in my house, and it is 90degrees outside, my computer resets
and of course..the reason why we're not going quad core
well..at least that's my personal opinion...as for the real reason...probally for profit...
Moore's Law has NOTHING to do with CPU speed.
/morz law/ prov. The observation that the logic density of silicon integrated circuits has closely followed the curve (bits per square inch) = 2^(t - 1962) where t is time in years; that is, the amount of information storable on a given amount of silicon has roughly doubled every year since the technology was invented. This relation, first uttered in 1964 by semiconductor engineer Gordon Moore (who co-founded Intel four years later) held until the late 1970s, at which point the doubling period slowed to 18 months. The doubling period remained at that value through time of writing (late 1999). Moore's Law is apparently self-fulfilling. The implication is that somebody, somewhere is going to be able to build a better chip than you if you rest on your laurels, so you'd better start pushing hard on the problem. See also
from a google search.
Moore's Law
You're planning on waiting more than a full year between computer upgrades? Are you sure you're on the right website?
How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
Dual cores processors seem to me like a pretty good alternative to a dual processor system. You don't have the hassle of 2 huge coolers blowing out hot air, the mainboards are don't have to be overpriced and it is already supported by all OS.
Some years ago I was thinking about getting a dual processor system. Alone the motherboard was two times as expensive as a similar single processor one, applications did not support it all and so on. I hope newer applications are ready for dual cores. Quake III was the first game I know that used two processors and finally I can consider that animated desktop background.
Is there a list which applications can effectively use dual cores besides obvious things like webservers?
Dual cores have been in the IBM PPC pipeline for quite a while - of course the (now old) Power4 arch has been multi-core all along.
In all probability the PPC little brother of Power5 (rumored to be called the 975) will debut at 90 nanometers and the next chip will be a ~60 nanometer dual core version possibliy called the 976.
Which if these will be called the G6 is left up to the reader as an exercise. My money is on the 976. Either way the PPC has some serious legs.
=tkk
Bill Gates - Creationist?!?
Just when I thought I had saved up enough money between upgrades to splurge on those fancy ramen noodles, you know, the one with the dried peas, this comes along.
Hey, Wal-Mart brand noodles are only 8 cents!
Its amusing to watch the chip manufacturers scramble desperately to meet the recommend specifications for Longhorn in time.
Oh, c'mon don't look at me like that. A slashdot story without some kind of Microsoft snipe just wouldn't be the same now, would it?
Alright, fine. I'll pick on SCO or AdTi next time. Sheesh. /me crawls back under his rock
She's built like a steak house, but she handles like a bistro....
actually there is plenty of bandwidth left in hypertransport to pull it off. also each cpu gets its own bank of memory. the design is superior to all others for SMP. even AMD's man CPU man says that at infoworld
AMD's dual-core server processors will share a single memory controller, Weber said. This won't create a bottleneck because a server with two Opteron chips, and therefore two memory controllers, already has more than enough memory bandwidth required to run that system, he said.
"It's always a juggling act to add a little more processing and a little more memory. Right now, we have plenty of memory and I/O bandwidth, so we're adding processing," Weber said.
The dual-core chips will work with current socket technology in motherboards that are rated for the specifications of the dual-core chips, Weber said. A BIOS change will be required, but otherwise the chips will work in the same sockets as single-core Opterons, he said.
ignorance is bliss. googlefiberatx.com
I understand your reasoning, but according to this article (I found the link on Ace's Hardware) the dual core chips will be compatible with current motherboards and sockets with as little as a BIOS flash (to recognise the new CPUID I assume). The downside of this is that the two cores will SHARE the dual channel memory bus. But because the bus is so effiencent, each core will probably STILL get more bandwidth than most P4s. At worst it shouldn't be much worse than having two single channel Athlon64s (which also are often faster than the P4). I think this is FANTASTIC news. For one thing, this means you could put FOUR CORES in that dual opteron SFF PC that was revealed a short while ago.
Really, it only makes sense. A dual channel processor has 939 pins, a single channel has 754 pins. So while some are power, you're looking at about 190 pins for the second memory channel. So that would mean that to have two cores on one die with their own memory channels, you'd need 1120 pins or so. That's a LOT of pins.
Instead of that enginering nightmare (you'd probably need 7 layer mobos to support that), we get drop in replacements that meet the same thermal requirements. Just think. You're dual operton not cutting the mustard any more? Buy two processors, drop 'em in, flash the BIOS, and now you've got FOUR processors without a new mobo or anything. All you'd have to worry about then is software licenses (unless of course you don't use any software that requirs that, for example you're all open source).
So to answer the grandparent's question, I'd say buy now. That said, I'm not sure if socket 939 will get dual cores or if it's only for 940s. I assume 939 will get them too.
Speculation: I'd like to know if the dual channel memory controler is shared by the two cores (like some kind of cross-bar architecture thing like nVidia used to promote) or if each core got exclusive access to one of the two channels. My guess is the former.
More speculation: Will there be a socket 754 dual core? That'd be cool, and I don't think the performance would be too much of a problem memory wise, unless you were doing memory intensive tasks. For CPU bound tasks I think you'd be fine.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
While the idea of dual core cpus is really cool, and will take over shortly due in part to the fact that we need something to do with all those extra transistors, I wonder why the focus of the industry is on chip multi-processors (CMP).
.
While CMP processors can give us rougly the same performance of a standard SMP system (somewhat faster due to interprocessor communication and shared memory, but also slower due to a larger memory bottleneck) I don't think that a CMP system would compete with a simultaneous multi-threading (SMT) solution.
While Intel's response to SMT (hyperthreading) has some benifits the performance of it is rather lackluster. The reason has more to do with their particular implementation. If you've read about the initial observations on SMT an 8-way SMT processor was shown to outperform a 4-way CMP processor. Now, I must note that the 8-way smt processor had more functional units then the cores in the 4-way CMP processor, but the overall area of the 8-way SMT processor would be much much smaller (far less structures need to be duplicated for SMT as opposed to CMP). For more information on this check out some of the papers at http://www.cs.washington.edu/research/smt/
What I don't understand is the insistance of the industry to use CMP first. From everything I've read, an 8-way SMT processor should take up less die space then a two way CMP processor. Even assuming that the 8 way processor contains more functional units. It kind of makes sense that a CMP processor is faster when there aren't enough threads to fully utilize a SMT processor (say only 2 or 3 threads that want full cpu usage). I guess SMT is a big chance in the model of programming and application development (I'm currently running research on the subject which is why I'm so interested in it). Is the reason to embrace CMPs simply because there's less new technology to add (they "just" have to interconnect two cores as opposed to adding the extra logic for SMT).
Does anyone else have any other opinions regarding this matter, or any idea why no one seems to be fully embracing SMT's potential.
Philip Garcia
The opteron (k8) has an integrated memory controller and up to three hypertransport links. In a dual k8 system, the cpus communicate over a single hypertransport link and are usually paired with their own memory bank. If one cpu needs data from the other's bank, it comes over the hypertransport link. Some cheap dual opteron boards save traces by pairing one cpu with all the memory banks - so every memory operation on the non directly linked cpu passes over the h-link.
The dual core cpu might have the pins for two seperate memory bank arrays or just the pins for one. Either way, the situation as far as dual k8s go is not really different from what we have already. Either way, it's a few steps above the p4 design: shared cpu bus to northbridge to memory. (yech! with a single proc, this introduces latency, with multiproc, you get contention and latency at every level)
AMD's cpu interconnect is so well thought out... it gives me the warm fuzzies pondering it:
A uniproc hammer needs one h-link for io.
A dually needs two per core: 1 for core to core, 1 for io (though all the io on all the boards I have seen feeds to only one proc's h-link... so that you don't lose PCI busses and such if you have only one proc installed, I suppose).
Quad and above requires three: each core links to two other cores, leaving one h-link per core for io. One could have a pci-e bus per proc, if one desired. But again, I haven't seen a design that doesn't feed all io into a single h-link.
Since no one uses the extra h-link anyway, a dual core package for a dual core system would need only one external h-link (saving some cash).
A quad core, dual package system would require three h-links feeding out of each package, though. But even then, the number of h-links laid out on the mobo is reduced and the whole shebang should be cheaper.
Intel's "one huge shared bus" + northbridge design is definitely being trampled...