One of the highlights of Hot Chips from 2019 was the startup Cerebras showcasing its product – a large ‘wafer-scale’ AI chip that was literally the size of a wafer. The chip itself was rectangular, but it was cut from a single wafer, and contained 400,000 cores, 1.2 trillion transistors, 46225 mm2 of silicon, and was built on TSMC’s 16 nm process.

The whole thing created a very big buzz, and later that year the company showed of the first system, CS-1, which is a 15U unit in order to power a single chip. Power consumption was in the 15 kW range, and the unit cost a few million. They are already being deployed by research institutions.

Initially Cerebras was set to announce its 2nd generation product here at Hot Chips this year, however the time-scale didn’t align exactly, so the company is instead going through its software procedures. But at the end of the slide deck, there’s a special slide with some details about the next generation.

Obviously when doing wafer scale, you can’t just add more die area, so the only way is to optimize die area per core and take advantage of smaller process nodes. That means for TSMC 7nm, there are now 850,000 cores and 2.6 trillion transistors. Cerebras has had to develop new technologies to deal with multi-reticle designs, but they succeeded with the first gen, and transferred the learnings to the new chip. We’re expecting more details about this new product later this year.

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  • Eulytaur - Tuesday, August 18, 2020 - link

    7nm is *that* good now? Wow okay
  • Loki726 - Tuesday, August 18, 2020 - link

    One small step towards ingot-scale computing...
  • SarahKerrigan - Tuesday, August 18, 2020 - link

    It is when you have a placemat-sized chip.
  • tipoo - Tuesday, August 18, 2020 - link

    I mean, sorta? It's effectively doing waver scale redundancy, it can work with some of the chips disabled
  • nandnandnand - Tuesday, August 18, 2020 - link

    Like tipoo said, it's made to work around defects. IIRC the stated core count is less than the amount on the chip.

    But even with that, TSMC 7nm yields are very good.
  • name99 - Thursday, August 20, 2020 - link

    Spoken in your best Norma Desmond voice:
    "7nm was always good. It was the competition that got bad"...

    It's hard to be certain, but TSMC ran 1.1M 7nm wafers in 2019. 2018 was ~.36M.
    So total number of wafers ever run is maybe ~2.5M?
    Then area of a wafer is 70 000mm^2.
    Total area capacity comes to ~177 B mm^2

    Point of this calculation is what's the average area of a chip? Obviously there are very big ones, up to ~700 mm^2. And very small ones (but no-one is making tiny chips on an expensive leading edge process). Average is probably a little larger than an A13, say ~100mm^2?
    Throw in scribe lines, circular edges, test wafers, and worst case yield is maybe 80%. Perhaps quite a bit higher -- the wafer numbers are very much guesses and could be 2M or less?
  • brucethemoose - Tuesday, August 18, 2020 - link

    This thing will have more SRAM than my phone has flash.
  • FunBunny2 - Tuesday, August 18, 2020 - link

    seems like the opportunity for our frenemies to build a machine to outwit the NSA's best. that may be good or bad, depending who's sitting at 1600.
  • TheJian - Wednesday, August 19, 2020 - link

    It would NEVER be good for someone to have better PC power than USA. PERIOD. Cut off your nose to spite your face I guess? Even with Obama as president (hated his policies), I rooted for his success. Well, not in destroying the country like he tried, but I mean in getting it RIGHT. I rooted for him to make the country MONEY and keep it SAFE, but he spent like crazy and lit the world and USA on fire with constant division and screwing allies right and left (black vs. white, heck every chance they got they made group vs. group).

    That said, I would never have wished for his administration to have crap computing power vs. others. We would lose a lot of crap if someone ever beats USA in tech. It's just dumb to wish for USA to do bad in any case. IF USA loses anything, everyone loses. WE are why YOU are not being run over, no matter where you are in the world. Vote for USA, or you are basically voting for your future problems. See our ships heading to S China sea? That's us defending YOU...and us, LOL, but you get the point, we lose you all lose the only question is how long it takes for you to CRY about it, and if you can recover once you pull your head out and VOTE USA again...LOL

    IE, Obama screwed middle east. Now Trump is bringing them all back together (israel, UAE, etc) and not bombing everyone in sight. Dems wanted a president that wouldn't start all kinds of wars. Well look at that, you got one...But you've been trying to derail him every since...ROFL. He's trying to make peace with everyone, but you hate him...ROFL. Lowest everyone unemployment until Covid, but you hate him. Best economy EVER, but you hate him. I could go on, but people keep wanting to cut off their nose to spite their face...LOL. Rooting for your president to fail is massively stupid.
  • 5080 - Wednesday, August 19, 2020 - link


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