NVIDIA's Fermi: Architected for Tesla, 3 Billion Transistors in 2010
by Anand Lal Shimpi on September 30, 2009 12:00 AM EST- Posted in
- GPUs
ECC Support
AMD's Radeon HD 5870 can detect errors on the memory bus, but it can't correct them. The register file, L1 cache, L2 cache and DRAM all have full ECC support in Fermi. This is one of those Tesla-specific features.
Many Tesla customers won't even talk to NVIDIA about moving their algorithms to GPUs unless NVIDIA can deliver ECC support. The scale of their installations is so large that ECC is absolutely necessary (or at least perceived to be).
Unified 64-bit Memory Addressing
In previous architectures there was a different load instruction depending on the type of memory: local (per thread), shared (per group of threads) or global (per kernel). This created issues with pointers and generally made a mess that programmers had to clean up.
Fermi unifies the address space so that there's only one instruction and the address of the memory is what determines where it's stored. The lowest bits are for local memory, the next set is for shared and then the remainder of the address space is global.
The unified address space is apparently necessary to enable C++ support for NVIDIA GPUs, which Fermi is designed to do.
The other big change to memory addressability is in the size of the address space. G80 and GT200 had a 32-bit address space, but next year NVIDIA expects to see Tesla boards with over 4GB of GDDR5 on board. Fermi now supports 64-bit addresses but the chip can physically address 40-bits of memory, or 1TB. That should be enough for now.
Both the unified address space and 64-bit addressing are almost exclusively for the compute space at this point. Consumer graphics cards won't need more than 4GB of memory for at least another couple of years. These changes were painful for NVIDIA to implement, and ultimately contributed to Fermi's delay, but necessary in NVIDIA's eyes.
New ISA Changes Enable DX11, OpenCL and C++, Visual Studio Support
Now this is cool. NVIDIA is announcing Nexus (no, not the thing from Star Trek Generations) a visual studio plugin that enables hardware debugging for CUDA code in visual studio. You can treat the GPU like a CPU, step into functions, look at the state of the GPU all in visual studio with Nexus. This is a huge step forward for CUDA developers.
Nexus running in Visual Studio on a CUDA GPU
Simply enabling DX11 support is a big enough change for a GPU - AMD had to go through that with RV870. Fermi implements a wide set of changes to its ISA, primarily designed at enabling C++ support. Virtual functions, new/delete, try/catch are all parts of C++ and enabled on Fermi.
Facebook
Twitter
RSS
415 Comments
View All Comments
AtwaterFS - Wednesday, September 30, 2009 - link
4 reals - this dude is clearly an Nvidia shill.Question is, do you really want to support a company that routinely supports this propaganda blitz on the comments of every Fn GPU article?
It just feels dirty doesn't it?
strikeback03 - Thursday, October 1, 2009 - link
I doubt SiliconDoc is actually paid by nvidia, I've met people like this in real life who just for some reason feel a need to support one company fanatically.Or he just enjoys ticking others off. One of my friends while playing Call of Duty sometimes just runs around trying to tick teammates off and get them to shoot back at him.
SiliconDoc - Thursday, October 1, 2009 - link
If facing the truth and the facts makes you mad, it's your problem, and your fault.I certainly know of people like you describe, and let's face it, it is one of YOUR TEAMMATES---
--
Now, when you collective liars and deniars counter one of my pointed examples, you can claim something. Until then, you've got nothing.
And those last 3 posts, yours included, have nothing, except in your case, it shows what you hang with, and that pretty much describes the lies told by the ati fans, and how they work.
I have no doubt pointing them out "ticks them off".
The simple fix is, stop lying.
Yangorang - Wednesday, September 30, 2009 - link
Honestly all I want to know is:When will it launch? (as in be available for actual purchase)
How much will it cost?
Will this beast even fit into my case...and how much power will it use?
How will it perform? (particularly I'm wondering about DX11 games...as it seems to be very much a big deal for ATI)
but heh none of these questions will be answered for a while I guess....
I'm also kinda wondering about:
How does the GT300 handle tessellation?
Does it feature Angle-Independent Anisotropic Filtering?
I could really couldn't give a crap less about using my GPU for general computing purposes....I just want to play some good looking games without breaking the bank...
haukionkannel - Thursday, October 1, 2009 - link
Well it's going to be DX11 card, so it can handle tessalation. How well? That remains to be seen, but there is enough computing power to do it guite nicely.But the big guestion is not, if the GT300 is faster than 5870 or not, It most propably is, but how much and how much it does cost...
If you can buy two 5870 for the prize of GT300, it has to be really fast!
Interesting release and good article to reveal the architecture behind this chip. I am sure, that we will see more new around the release of Win7, even if the card is not released until 2010. Just to make sure, that not too many "potential" customers does not buy ATI made card by that time.
Allso as someone said before this seams to be guite modular, so it's possible to see some cheaper cut down versions allso. We need competition to low and middle range allso. Can G300 design do it reamains to be seeing.
SiliconDoc - Thursday, October 1, 2009 - link
Well, that brings to mind another anandtech LIE.--
In the 5870 article text post area, the article writer and tester, responded to a query by one of the fans, and claimed the 5870 is "the standard 10.5 " .
Well, it is NOT. It is OVER 11", and it is longer than the 285, by a bit.
So, I just have to shake my head, and no one should have wonder why. Even lying about the length of the ati card. It is nothing short of amazing.
silverblue - Thursday, October 1, 2009 - link
http://vr-zone.com/articles/sapphire-ati-radeon-hd...They say 10.5".
SiliconDoc - Thursday, October 1, 2009 - link
I'm sorry, I realize I left with you in the air, since you're so convinced I don't know what I'm talking about." The card that we will be showing you today is the reference Radeon HD 5870, which is a dual-slot graphics card that measures in at 11.1" in length. "
http://www.legitreviews.com/article/1080/2/">http://www.legitreviews.com/article/1080/2/
I mean really, you should have given up a long time ago.
silverblue - Friday, October 2, 2009 - link
Anand, could you or Ryan come back to us with the exact length of the reference 5870, please? I know Ryan put 10.5" in the review but I'd like to be sure, please.It's best to check with someone who actually has a card to measure.
silverblue - Friday, October 2, 2009 - link
You know something? I'm just going to back down and say you're right. You might just be, but I couldn't give a damn anymore.