Thursday, November 18th 2010

AMD Zambezi ''Bulldozer'' Desktop CPU Roadmap Revealed
AMD's next-generation PC processor architecture that seeks to challenge the best Intel has, codenamed "Bulldozer", is set to make its desktop PC debut in 2Q next year, with a desktop processor die codenamed "Zambezi". AMD is seeking to target all market segments, including an enthusiast-grade 8-core segment, a performance 6-core segment, and a mainstream 4-core segment. The roadmap reveals that Zambezi will make its entry with the enthusiast-grade 8-core models first, starting with 125W and 95W models, trailed by 6-core and 4-core ones.
Another couple of architectural details revealed is that Zambezi's integrated memory controller (IMC) supports DDR3-1866 MHz as its standard memory type, just like Deneb supports DDR3-1333 MHz as its standard. DDR3-1866 MHz, or PC3-14900 as it's technically known, will churn out 29.8 GB/s in dual-channel mode, that's higher than triple-channel DDR3-1066 MHz (25.6 GB/s), which is Intel Core i7 LGA1366 processors' official memory standard. The 8-core and 6-core Zambezi models feature 8 MB of L3 cache, while the 4-core ones feature 4 MB. Another tidbit you probably already knew is that existing socket AM3 processors are forwards-compatible with AM3+ (Zambezi's socket), but Zambezi processors won't work on older AM3/AM2(+) socket motherboards.
Source:
ATI Forum
Another couple of architectural details revealed is that Zambezi's integrated memory controller (IMC) supports DDR3-1866 MHz as its standard memory type, just like Deneb supports DDR3-1333 MHz as its standard. DDR3-1866 MHz, or PC3-14900 as it's technically known, will churn out 29.8 GB/s in dual-channel mode, that's higher than triple-channel DDR3-1066 MHz (25.6 GB/s), which is Intel Core i7 LGA1366 processors' official memory standard. The 8-core and 6-core Zambezi models feature 8 MB of L3 cache, while the 4-core ones feature 4 MB. Another tidbit you probably already knew is that existing socket AM3 processors are forwards-compatible with AM3+ (Zambezi's socket), but Zambezi processors won't work on older AM3/AM2(+) socket motherboards.
123 Comments on AMD Zambezi ''Bulldozer'' Desktop CPU Roadmap Revealed
I really can't wait to see how they do against sandy bridge even if I'm unsure if i can wait long enough, but worst case is a buy something from sandy bridge and find out i should sell it and go with a bulldozer core... at least i could keep the ram :laugh:
I will be interested however in how their 6 core offerings compete with the current Intel Gulftown models because if they are close, it's fairly certain that Intel will remain competative with their future releases.
Splitting a thread over multiple integer cores would create a scheduling nightmare. You'd spend so much time going back and forth over the two cores that you would lose cycles and efficiency.
Imagine this scenario:
A+B=C
C*4=D
D+E=F
F*G=H
H+I=J
It is all incredibly linear. You could take A+B and run it on one core, but the second core handling that thread would have to wait to get C, so you lose a cycle for that second core. Then you do C*4 on the second cycle, but that second core is still sitting idle. But you probably lose a cycle of overhead now because the second core is saying "do you have anything for me"? The checksum to sync the two cores takes a cycle, so now you are at 3 cycles and you have only run 2 instructions on the 2 cores, and one has sat idle 100% of the time.
Obviously you can see where this goes nowhere. Fast. The only place it would work is if a thread was extremely parallel, but there will still be some checksum/synchronizaiton that will eat up overhead and create latency/inefficiency.
So then you think, well, if we have inefficiency and pipelines sitting idle, why not use SMT to load multiple threads on a single core and take advantage of the pipeline gaps/stalls?
Then you are breaking up all of the threads across multiple cores, creating gaps in pipelines and then trying to load multiple threads to fill in those gaps. Definitely not efficient. I am not a lurker, I contribute ;)
Toodles!
:laugh:
EDIT:, yeah, I'll give you that, JF-AMD, you are always on top of the Bulldozer threads, not quite lurking, and I personally appreciate the info.
But ya know, I'll take the contribution of a board and a few cpus...:roll:
I personally don't care if it's server or desktop...I just need a board with an included PCI-E 16x slot. Those Tyan G34 boards with 4x PCI-E slots seems right up my alley, actually.
It's really the entry price that has most of us stay away from server-based products, even though they seem to be built for a far greater workload. For me, really, it's the memory pricing.
Anyhow, crunchers need cores.
But if you find some of my posts from 5-6 years ago, you'll see that i was posting aobut every house having a server, and then using "thin" clients to actualyl access that server and it's grunt. If that server with 4x vgas could run 4x games...served to various parts of my house, man, I'm in. I know the grunt is there...could get 24 cores, and 4x vgas...
I've got 4 kids, so need 6 PCs. But 6 full-size pcs genreate alot of heat, and suck back alot of power, too.
House is already wired for it, too. All i need is to dump a server into the mechanical room, ethernet and such is all there and waiting.
Oh, and I'm special, you know. Just because you help me out, doesn't mean others are special too...:roll:
Don't let the fact that I'm special in the head deter you. :laugh: Heck, I knew who you were before anyone else here. LOL.
Now, where's my cpus?
:laugh:
Plus ATI raped me on a X1800XT, big time, and my ass still hurts, I sold it to a work intel build for $50 a short while later. Then I coudn't even fold on it.
I admit if the 8 core bulldozers (or something from sandy bridge) overclock well on water it will be enough to push me to my first custom loop.
I have been loving the H50 but it's hardly water cooling compared to a custom loop with a nice fat 480mm rad :D
The poor support, and broken promises type of continued fucking is starting to piss me off. Unless AMD comes out with something great I will have a Intel/Nvidia machine, Adobe acceleration, faster CPU based rendering, better memory support. I spent money again and again and each time the promises ATI/AMD make are broken, CCC GPU based encoding? Sure for a few formats that there are freeware converters everywhere for, so I can convert that already small mpg onto my phone. How about something hard like the ability to hardware render M2TS from my canon? Nope, gotta run that on the CPU. Oh yeah, its slower than two series old Intel chips. That is unless you want to purchase this software, and oh, it only works on some things, so you still need all these other codecs that don't work together and cause issues.
You want to accelerate videos and upscale them with the hardware you purchased? That costs extra.
I really hope that whatever brands your next upgrade involves that things work out better than they have been for you.
We can only hope...
I wanna build a server :p
Looking at the preliminary reviews of Brazos on Anandtech it looks like AMD has spent the last 5 or 6 years bragging and not actually doing any work. All this is, is a HD5000/HD6000 GPU strapped to an underpowered and poorly designed CPU. If that's all Fusion is meant to be then sorry mate, but I'm going Intel. I have been waiting 5 years for Fusion and to see it's not remotely what they were cracking it up to be, it just seems like AMD made a processor that would have been good 5 years ago but they have held it back for far too long.
This would have been a good fight against Nehalem, but Sandy Bridge? Ha. And don't go on to me about Intel GMA being a piece of fail because obviously you haven't read the reviews of the early Sandy Bridge: that thing takes on low end HD5000 series cards, and those things aren't too bad.
AMD, just release Fusion already so we can see it fail. It's clearly ready for mass market and has been for quite some time.