AzN
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- Nov 26, 2001
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Originally posted by: BFG10K
What you call ?bandwidth happy? is actually the norm for DX10 parts because they generally have enough bandwidth so that it?s not the primary limiting factor. In essence you agree with me, but try to word it in a way so that it appears you disagree.
Again I?ll ask whether you consider the 4770 to be bandwidth happy? It must be according to your definition because it?s faster than the 4830 while experiencing a reduction in bandwidth.
Just because you own a GTX series or your prior Ultra doesn't mean all dx10 parts have generally enough bandwidth. G92 is one of those cards that lacks enough bandwidth.
No I don't consider 4770 to be a bandwidth happy card. You are obviously getting confused. It's faster than 4830 because it has faster shader clocks first off. Second it has higher texture fill and pixel fill because of core clocks. Bandwidth only determines how fast those pixels and textures go in and out of graphics memory a litttle more on higher resolutions or with AA. Just because it has slightly lower bandwidth does not mean it will be slower than 4830.
Again back to my explanation and here's an example.
HD4830
9200 Mpixels/s
18400 Mtexels/s
736 GFLOPS
HD4770
12000 Mpixels/s
24000 Mtexels/s
960 GFLOPS
Let say 4830 is bottlenecked by bandwidth by 10% and 4770 is bottlenecked by 20% and you would get something like this. Again there are variables in higher resolutions, settings, etc where those numbers would fluctuate...
HD4830
8280 Mpixels/s
16560 Mtexels/s
736 GFLOPS
HD4770
9600 Mpixels/s
19200 Mtexels/s
960 GFLOPS
While I?m not disputing the accuracy of your figures, they?re clearly an outlier. This is very obvious by the fact that the 8800 GTS 640 MB has more bandwidth that the 8800 GT, but it?s also slower overall, even with AA. If the 8800 GT was primarily limited by bandwidth, there?s no way it could be faster: http://www.behardware.com/arti...a-geforce-8800-gt.html
I guess my benchmarks don't count but yours do?
Although 8800gt is severely bottlenecked by bandwidth it can still beat 8800gts 640 mb because 8800gt has 112SP 56TMU while 8800gts has 96SP wtih 24TMU. Look at the easy picture like example above. That should explain why 8800gt is able to beat 8800gts. Now if 8800gt had more bandwidth it can stump 8800gts "further".
You appear to be typing responses that have nothing to do with what you quoted. Let?s go back to the beginning:
I stated the 4850 isn?t constrained by bandwidth because it beats the Ultra with AA despite having around half the bandwidth, and also that it?s about three times faster than the 3870 with AA, with less bandwidth again. Therefore, the 4850 is not hamstrung by bandwidth.
You then posted a slide showing ROP resolve being doubled and told us that is why the card does so well with AA.
I acknowledged this but then pointed out since improvements in ROPs are dramatically raising AA performance, this means bandwidth isn?t the limiting factor given it?s decreased from either the 3870 or the 8800 Ultra, yet the card is still faster with AA.
So again I?ll ask how an improvement to ROPs can show such performance gains with AA if the 4850 is limited by bandwidth like you claim? How can the reduction of bandwidth ? the aspect you claim the card is primarily limited by and influences AA performance - increase AA performance?
It?s a very simple question, so please address it instead of typing multiple sentences of irrelevant rhetoric. Thanks.
Obviously a clear example does not help you understand but confuses you even further. So I'll make it simpler by answering your question.
3870 AA is broken. It has less than 1/2 texture fillrate and shader performance compared to 4850. 3870 was never limited by bandwidth because it never had the fillrate for the need for more bandwidth. This was prevalent when ATI cut 3870 bandwidth by 50% and still perform exactly same as 2900xt. With the ultra I gave you a clear example which you can't seem to take in. Nothing I can do about that.
Why are you talking about made up numbers when we have actual benchmarks proving you wrong?
that's why it's called an example. you do know what an example is don't you?
Oh yes, the amazing 3DMark, which told us the 2900XT was faster than the 8800 GTX. Oh wait, that?s the complete opposite of reality when running games. Much like your theoretical figures which you made up.
IF you have a problem with techreport or their affiliates I suggest you take it up with them. Tell them who you are and where you write your articles and that you have problems with their conclusions. Oh BTW your partner has no problems with 3dmark as he uses this benchmark to determine his conclusions.
You have no idea what tests I?ve done given I haven?t released all of the results to the public. Furthermore there?s a plethora of tests I can link to that were done by other reviewers that back my claims.
The problem is that you don?t acknowledge such a broad range of tests disproving you but instead cling to your own tests as the sole form of evidence. Again, my tests simply confirm what other reviewers are saying so that makes your tests the outlier, not mine.
I don't know what tests you've done but I do know what cards you've had. You had an ultra and a 4850 for a short time then GTX260 and finally GTX 285. Out of all those cards except for 4850 they were all bandwidth happy cards.
Your tests are correct and mine is wrong even though the card I tested was a G92 which has everything to do with this thread while your tests consist of G80, RV770, GTX series mostly bandwidth happy cards. Clearly you are the one that have a problem with accepting other people's findings unless it was already been done before by other web sites clearly that's all you ever write your articles on.
How do you know it could use 25% more memory? Where did this figure come from?
Again it?s not hard; just overclock the 4850?s core and witness an almost linear performance increase without touching the memory at all. Heck, ATi have done it for you with the 4870 where the performance gain in games basically matches the core performance improvement, thereby proving most of the extra bandwidth over the 4850 is simply not needed.
I'm just making a educated guess here considering 4870 performance doesn't improve with more bandwidth while 4850 does.
This might be too much for you to swallow. Here is gainward 4850 clocked @ 4870 core clocks and memory @ 1200mhz going up against a stock 4870.
http://www.xbitlabs.com/articl...1024mb-gs_7.html#sect1
Again 4870 is still considerably faster than 4850 at those clocks.
The 4850 beating the 4770 could be due to lots of reasons but you certainly can?t automatically infer it?s from more bandwidth. Actually the three cards slot in the order of their shader performance which is something similar with the G80 and G92 line.
OTOH after reducing the bandwidth on the 4770 it?s still faster than the 4830 with more bandwidth, you can safely conclude that the 4770 isn?t primarily limited by bandwidth.
But then again we are talking about AA benchmarks here where shader doesn't matter much even in your ultra AA core/shader/memory clock findings. Since 4770 push more pixels and you say 4770 isn't really bottlenecked by bandwidth why does it lose in AA benches?