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Larrabee Based On a Bundle of Old Pentium Chips
arcticstoat writes "Intel's Pat Gelsinger recently revealed that Larrabee's 32 IA cores will in fact be based on Intel's ancient P54C architecture, which was last seen in the original Pentium chips, such as the Pentium 75, in the early 1990s. The chip will feature 32 of these cores, which will each feature a 512-bit wide SIMD (single input, multiple data) vector processing unit."
Ah the dreams of the past, a beowulf cluster of old computers come to life :)
Larrabee is the codename for a discrete graphics processing unit (GPU) chip that Intel is developing as a revolutionary successor to its current line of graphics accelerators. The video card containing Larrabee is expected to compete with the GeForce and Radeon lines of video cards from NVIDIA and AMD/ATI respectively. More than just a graphics chip, Intel is also positioning Larrabee for the GPGPU and high-performance computing markets, where NVIDIA and AMD are currently releasing products (NVIDIA Tesla, AMD FireStream) which threaten to displace Intel's CPUs for some tasks. Intel plans to have engineering samples of Larrabee ready by the end of 2008, with public release in late 2009 or 2010.[1]
According to Wikipedia http://en.wikipedia.org/wiki/Larrabee_(GPU)
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It's one of the larger cities in Wyoming. Get with it. ;)
Intel... where quality is job 0.9995675!
Power can come from multiple sources. In this case, you have a 150W power connector (probably a 6pin PCIe one), and another 75W one (yet another 6pin PCIe). The remaining 75W comes from the PCIe connector itself.
Nothing terribly unusual - a number of cards are coming out in configurations like this, and 300W for a video card is starting to become the norm, depressing as it is.
It's one of the larger cities in Wyoming. Get with it. ;)
Only if you have a head cold.
I doubt it. Maybe they mentioned the Pentium as an example to explain an in-order superscalar architecture as opposed to more modern CPUS.
-There is a lot of overheard in the P54C to execute complex CISC operations that are completely useless for graphic acceleration.
-The P54C was manufactured in a 0.6micron BiCMOS process. Shrinking this to 0.045micron CMOS (more than 100x smaller!) would require a serious redesign up to the RTL level. Circuit design had evolve with process technology.
-a lot more...
Larrabee is going to be Intel's next creation in the GPU world. A many core GPU which has the following peculiarities :
- fully compatible with x86 instruction set. (whereas other GPU use different architecture, and often instruction sets that aren't as much adapted to run general computing).
Thus, the Larrabee could *also* be used as a many core main processor (if popped into a quick path socket) and used to execute a good multicore OS. Something that's not achievable with any current GPU (both ATI's and nVidia's completely lack some control structures - both are unable to use subroutines and everything must be in-lined at compile time)
- unlike most current Intel x86 CPUs, features a shallow pipeline, executing instruction in-order. Hence, the Larrabee (and the Silverthorne which also have such characteristics) are regularly compared with old Pentiums (which also share those characteristics) since the initial announcement and including in TFA.
- feature more cores with narrower SIMD : 32 cores able each to handle 16 32bit float simultaneously. Whereas, for exemple nVidia's CUDA-compatible GPU have up to 16 cores only, but each able to execute 32 threads over 4 cycles and keep up to 768 threads in flight.
This enable Larrabee to cope with slightly more divergent code than traditional GPUs and make it a good candidate to run stuf like GPU accelerated RayTracing.
Hence all the recent technical demos running Quake 4 in raytracing mentionned on /.
That's for what Intel tells you.
Now the old and experienced geek will also notice that Intel has only kept making press releases and technical demo running on plain regular multi-chip multi-core Intel Cores (just promising that the real chip will be even better than the demoed stuff).
Meanwhile, ATI and nVidia are churning new "half"-generations each 6 months.
And the whole Larrabee is starting to sound like a big vaporware.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Yes, 32 x 600MHz x 1MIP/MHz @ 0.5W == 19.2 GIPS@16W.
Meanwhile...
32 x ???MHz (Unknown, but likely to be 900+ to be competitive with current designs) x 3+MIPS/MHZ + 32 x 512-bit SIMD units = OMGWTFHAX @ 300W.
Seriously. The "Pentium" base of this design is damned near irrelevant. At this point, all it's doing there is scheduling execution on the SIMD units. If you've seen any modern GPU designs, they're basically hugely parallel cores attached to a few "director" cores which puts everything where it needs to go. The original Pentium is probably the most powerful CPU with the least complicated design on the process, with the least amount of legacy MMX cruft.
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http://babelfish.yahoo.com/translate_url?doit=done&tt=url&intl=1&fr=bf-home&trurl=http%3A%2F%2Fwww.heise.de%2Fct%2F08%2F15%2F022%2F&lp=de_en&btnTrUrl=Translate
Actually, they got the "Gelsinger said so" remark from Expreview, itself a Chinese site:
http://en.expreview.com/2008/07/07/larrabee-unleashes-2-tflops-capacity (note they curteously attached the Larrabee board diagram leaked from a while back):
"Gelsinger said the Larrabee will be a 45nm product featuring SIMD technique, 64-bit address. Besides, 32 of cores runing at 2.00 GHz will unleash 2 TFLOPS capacity, twice as much as the RV770XT."
But did Gelsinger really SAID those things?
Here is the Google translation of the same Heise article: http://translate.google.com/translate?u=http%3A%2F%2Fwww.heise.de%2Fct%2F08%2F15%2F022%2F&hl=en&ie=UTF8&sl=de&tl=en
It seems that no matter which crappily translated version of the German article one looks at, it appears that Gelsinger said no such thing... The part about Larrabee containing P54C cores was clearly in a separate paragraph, written after a speculative question.
So I guess Expreview THOUGHT Pat said something after it took a too-short of a look at the Heise article, after which CustomPC sensationalized the whole thing, not really bothering to actually read even the translated link it posted. Now, some random Slashdotter is doing the same curtesy.
There you go, folks- Internet reporting.
I#m very sceptic about Intes
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Sometimes, life itself is sarcasm...