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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Stas - Sunday, February 14, 2010 - link
Awesome. Thanks!Adul - Sunday, February 14, 2010 - link
Really helps pass the time at work today. :) Keep it up.Btw when can we expect to see the new site launch?
aapocketz - Sunday, February 14, 2010 - link
[quote]I was convinced that ATI had embraced a new, refocused approach to GPU design, only to learn that they nearly threw out all of the learnings with the RV870. [/quote]It sounds like they have had some successes trying different techniques, but without stability in their production process it is hard to repeat success. I understand that they require constant innovation to stay competitive, but throwing out whole processes seems chaotic to me. I would like them to refine and improve successful processes rather than toss everything every time a new business guru is in charge.
Also half of their effort was all about openness and collaboration. The opening up of the PRS document so that "everyone was involved in the process" seems to clash with the hyper-secret groups where "AMD has since incorporated much of Carrell’s brand of information compartmentalization into how it handled other upcoming features." This seems like a recipe for disaster to me. Which is it, broad openness, collaboration and consesus; or secret teams that have no idea what the other teams are doing?
SuperGee - Sunday, February 14, 2010 - link
The story told us that they didn't know it will become a succes because these desision where made before RV770 release. So doing the high risk choice again. Wasn't a nobrainer. But a risky choice. We know that it turn out good now.mckirkus - Sunday, February 14, 2010 - link
It's kind of funny that you're not yet running one of these companies yet Anand.One of the reasons I check this site on a daily basis is because you also seem to also get the business side of the equation. It's downright refreshing to see someone bridging that gap. You pretty much saved the Vertex from self destruction. I'd like to see what interesting things you could build us if you put your mind to it.
deputc26 - Sunday, February 14, 2010 - link
Articles like these are what differentiate AnandTech from all the other sites out there. AnandTech goes from being one of the best review sites out there to something special.Beyond excellent, thanks Anand.
rickyv - Sunday, February 14, 2010 - link
As a loyal follower of your website for the past 15 years, I also felt that I just had to register and compliment you on an excellent article.With the rapid advancement of technology, it is very easy just to get caught up in the PR and marketing hype or focus only on the numbers game. We often lose sight of the fact that it is teams of dedicated people who make this possible. You have always had the ability to bring out the "human" side to this. I have not seen this on any other site nor in printed form (that is not an unashamedly PR marketing exercise).
Thanks for staying true to your roots by giving honest opinions of the technology that you review. The latest releases are not necessarily always the greatest (as much as the marketing departments would like us to believe :-) )
krish123 - Sunday, February 14, 2010 - link
After i read the article, I found that "Engine is running well and firing on all the cylinders", It can create better products in the future, I can trust and buy ATI products, hope they deliver better products in the future for my upgrade."Kudos to Anand for the excellent article".
By the way graphics card is a product, not just hardware, it has to work in tandem with the software, its better ATI put some more effort on the driver/software side and fix all the issues.
Krish
smartalec - Sunday, February 14, 2010 - link
"When companies like AMD and NVIDIA do a product the engineers don't know all of the answers, and the knowledge they do have isn't binary - it's probability, it's weight, it's guesses. Sometimes they guess right, and sometimes they guess very wrong. The best they can do is to all weigh in with their individual experiences and together come up with the best group of guesses to implement."I'm afraid this is how all engineering works. Project managers think that engineers can predict the future. That we know exactly how much time it'll take, and how much risk a given feature will bring.
We don't. There's a lot of educated guesses. Sometimes we're pleasantly surprised that what we thought was a tough problem wasn't. Sometimes we're the bearer of bad news-- something we assumed would be trivial wasn't.
My most frustrating issues aren't technical at all. I ask for 2000 hours, and are given 1000. Or are given 2 engineers instead of 3, and told-- figure out a way to get it done anyway, without impacting schedule.
Great article Anand.
mckirkus - Sunday, February 14, 2010 - link
Any decent project manager (I do software) reviews the risks up front with the engineers before building the project plan / timeline.The fact that most project managers don't really understand the products they manage is the rule not the exception. The problem is that great engineers don't always make great PMs. Having a good tech lead helps.