The RV870 Story: AMD Showing up to the Fight
by Anand Lal Shimpi on February 14, 2010 12:00 AM EST- Posted in
- GPUs
Adjusting Trajectory & Slipping Schedule
Carrell didn’t believe in building big chips anymore. It wasn’t that it was too difficult, it’s that it took too long for a $600 GPU to turn into a $200 GPU. AMD believed that the most important market was the larger (both in quantity and revenue) performance mainstream segment.
Rather than making the $200 - $300 market wait for new technology, Carrell wanted to deliver it there first and then scale up/down to later address more expensive/cheaper markets.
The risk in RV770 was architecture and memory technology. The risk in RV870 was architecture and manufacturing process, the latter which was completely out of AMD’s control.
Early on Carrell believed that TSMC’s 40nm wasn’t mature enough and that when it was ready, its cost was going to be much higher than expected. While he didn’t elaborate on this at the time, Carrell told me that there was a lot of information tuning that made TSMC’s 40nm look cheaper than it ended up being. I'll touch on this more later on in the article.
Carrell reluctantly went along with the desire to build a 400+ mm2 RV870 because he believed that when engineering wakes up and realizes that this isn’t going to be cheap, they’d be having another discussion.
In early 2008, going into Februrary, TSMC started dropping hints that ATI might not want to be so aggressive on what they think 40nm is going to cost. ATI’s costs might have been, at the time, a little optimistic.
Engineering came back and said that RV870 was going to be pretty expensive and suggested looking at the configuration a second time.
Which is exactly what they did.
The team met and stuck with Rick Bergman’s compromise: the GPU had to be at least 2x RV770, but the die size had to come down. ATI changed the configuration for Cypress (high end, single GPU RV870) in March of 2008.
And here’s where the new ATI really showed itself. We had a company that had decided to both 1) not let schedule slip, and 2) stop designing the biggest GPU possible. Yet in order to preserve the second belief, it had to sacrifice the first.
You have to understand, changing a chip configuration that late in the game, 1.5 years before launch, screws everything up. By the time RV770 came out, 870 was set in stone. Any changes even a year prior to that resets a lot of clocks. You have to go back and redo floorplan and configuration, there’s a lot of adjusting that happens. It takes at least a couple of weeks, sometimes a couple of months. It impacted schedule. And ATI had to work extremely hard to minimize that where possible. The Radeon HD 5870 was around 30 - 45 days late because of this change.
Remember ATI’s nothing-messes-with-schedule policy? It took a lot of guts on the part of the engineering team and Rick Bergman to accept a month+ hit on redesigning RV870. If you don’t show up to the fight, you lose by default, and that’s exactly what ATI was risking by agreeing to a redesign of Cypress.
This is also super important to understand, because it implies that at some point, NVIDIA made a conscious decision to be late with Fermi. ATI wasn’t the only one to know when DX11/Windows 7 were coming. NVIDIA was well aware and prioritized features that delayed Fermi rather than align with this market bulge. GPUs don’t get delayed without forewarning. AMD risked being late in order to make a smaller chip, NVIDIA risked being late to make a bigger one. These two companies are diverging.
The actual RV870
Engineering was scrambling. RV870 had to be a lot smaller yet still deliver 2x the computational power of RV770. Features had to go.
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wlee15 - Sunday, February 14, 2010 - link
The USS Hornet is a carrier not a battleship.For shame Anand For Shame!
Anand Lal Shimpi - Monday, February 15, 2010 - link
wow - you're totally right, I can't believe I made that mistake. Looks like Ryan or Jarred caught it shortly after it went live though, whew :)And yes, for the record, I know the difference between an aircraft carrier and a battleship :)
Take care,
Anand
just4U - Tuesday, February 16, 2010 - link
LIES!!!!(hah)
Sahrin - Sunday, February 14, 2010 - link
Thank you - I was worried I'd be the only one to point this one out.Thank you Anand! This stuff is incredible. Just a few weeks ago I was looking back on the RV770 article and wishing it could be done again.
Kudos as well are due to AMD's PR guys - for having the courage to let the engineers sit down with the press, instead of needing to be there as minders. I guarantee you that every single time, the same story told by a marketer of a product and by the guy whose passion created the product will be a thousand times more effectively conveyed by the engineer. Marketers have value - I'm not trying to write them off.
I don't know what I can do for AT and AMD to thank them for making articles like this happen. Aside from buying Cypress and being a reader - but if there is anything we can do to ensure these articles keep coming (bombard Meyer with Faxes?) let me be the first to sign up. (And maybe if we could get access to AMD's CPU guys as well, to provide a balance to the excellent information we get from Intel).
Dianoda - Sunday, February 14, 2010 - link
This article was a real treat, keep 'em coming...dzx - Monday, February 22, 2010 - link
I created an account just to give thanks for such a well written, informative article. I can sense you have just as much passion for the technology as the engineers and architects who create it. Simply a pleasure to read.gralex - Friday, February 26, 2010 - link
Thanx. I have nothing more to add that hasn't been said already in the above comments, just thanks.As for ATI vs. NVIDIA, maybe i'm believing the hype but AMD seems awfully conservative at the moment. It's totally working for them, of course, but I'm liking the whole CUDA, Tegra2, Ion, Optimus momentum Nvidia might finally be gaining right now. Obviously they messed it up with a ton of rebranding making a 5xxx purchase a no-brainer right now... I just LOVE the way Nvidia was looking cornered and thought up a number of ways to get out. I hope these two keep up the healthy rivalry for many years to come, for ALL of us:-)
phaxmohdem - Sunday, February 14, 2010 - link
Wow. This was perhaps the first article I've read in a long time I read cover-to-cover, and couldn't put down. AT is my favorite tech review site, but I find myself reading the first two pages or so, skipping around to various benchmark pages, then reading the summary. This piece was remarkably intriguing and thought provoking. I look forward to the RV970 story, or perhaps better yet, the GF100 story.Keep em coming!
gimmeausername - Sunday, February 14, 2010 - link
Did you just say RV970?I think you've just made some folks at AMD flip out by using that code name. :D
coolhardware - Sunday, February 14, 2010 - link
As others have mentioned, articles like this one really put Anandtech head and shoulders above the competition. It is so very interesting to find out the real world story behind the video cards. What a wonderful Valentine's Day treat :-).Thanks for all your hard work Anand, I really appreciate it!