Comments on: AMD to Nvidia: Two chips are better than one

AMD's new dual-chip graphics technology matches Nvidia at high end.

[Lerianis]

Something doesn't seem right there, in all honesty. 2 chips only get 150% of the performance of 1 chip? Shouldn't that be twice the performance, in all honesty, with two chips? Seems like this might be a problem with drivers, that maybe the drivers aren't well-written enough to take advantage of two physical boards.

[gerrrg]

two chips are not 1 chip...they are separated by a long distance, in comparison to the distance of circuits on a single chip.

[Imalittleteapot]

It's the nature of using two chips to do one task. If you actually have two separate tasks you're good, but you don't always have two separate tasks. There's many things that can cause multiple CPUs to take a performance hit.

Consider what I'll call the 1.5 task problem if you will. Two CPUs have two separate tasks, but at some point these two separate tasks need to work with the same data. A very over simplified, hypothetical example follows.

CPU 1 is rendering objects with texture maps while CPU 2 is writing those texture maps to the video ram at the same time. Perhaps receiving them from the game. They're both working on two separate things very nicely. Now all of a sudden CPU 1 needs a texture map that CPU 2 has only written half of. What do you do? Well, CPU 1 can go ahead and draw with half a texture and it will look like crap, or it can wait for CPU 2 to finish up its work, but that's where it loses performance. For a millisecond or so CPU 1 doesn't have anything to do. You're back down to one CPU. When these wait conditions happen every few milliseconds or more your average performance takes a hit real quick.

[The_Decider]

In only extremely rare cases do you ever get xN performance where N is the number of chips. 150% boost on 2 chips is outstanding. On desktop processors, you often get a slowdown using multiple processors, especially with 'normal' desktop apps. Communicating accross cores and maintaining data integrity is expensive, even in GPU's.

[smokified]

You apparently have no idea how anything works at all.

[Imalittleteapot]

smokified:

That's a little rude. Maybe we should just stick to criticizing each other's opinions and spelling like we always do. If someone pops on in with a generally dumb opinion that's one thing, hammer away, but when someone stops by just trying to figure out why something works differently than the way they thought it would, you could be little more constructive don't you think? Gotta tell ya, I'll respect someone that admits something they don't know on a board looking for some insight long before I'll respect someone that just throws out random insults. Especially since I've been that guy on the boards looking for answers. Haven't you?

[laynemoseley]

It's called parallel processing. It's a extremely hard things to do. It's amazing that they can now get about 1.8 times the performance out of 2 chips.

[k2dave]

Another way to look at it is if you have job for a man. Chopping wood 2 men should get the job done in half the time as one. But if the task was to write a story, 2 men would have to coordinate sections to join together into one, taking a performance hit. Or if you are doing some fine detailed work perhaps fixing a watch, in this case really only one man could actually work as the second could only get in the way.

[inachu]

I stopped using ATI 2 years ago purely because ATI video cards create way more heat than Nvidia cards.

[sportbikerr1]

Ironic how it was recently nvidias chipsets that were getting nuked from over heating ;-)

[smokified]

Sportbikerr1, Please provide something that backs up that claim. I have been using nVidia since they bought 3dFX and I have yet to come even near overheating. The only overheating issue I have ever had from nVidia was when running 2 8800s in SLI and it was my case that was causing the overheating due to crappy fans.

[pmfjoe]

The performance hit comes in both ATI Crossfire implementations and nVidia SLI. In previouse X2 cards ATI just used on board Crossfire.

[cswifty2]

ATI more hot? R U serious? was this 5 years ago when you switched. If you haven't notticed, ATI has run way more cool than Nvidia for quite some time

[smokified]

That is beause their cards do half as much....

[smokified]

ATI/AMD has been a failing entity for a while now. Nothing they make comes close to the performance and efficiency as it's counterpart nVidia product. After AMD takes the time to "catch-up", nVidia has already had the time to move on to the next generation. AMD continues to play catch-up while nVidia continues to make groundbreaking developments.

ATI is just a cheaper alternative to real gaming hardware.

[smokified]

Lets also not forget that it is taking 2 chips and a newer memory standard for AMD to do what nVidia does with 1 chip and GDDR3 and GDDR4 standards.