Why is ATI 3870 so slow?

harly2

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Look at the ATI 3870's specs. Its a beast!

- Higher frequency's across the board (GPU,SHADER,MEMORY).

- 80 Vertex Pipelines as opposed to 28 from 8800GT

- More raw Processing power then 8800 GT

- Higher Memory bandwidth 72GB vs 56GB

- 320 Stream Processors!!! vs. 112 from 8800GT

It has one lower spec, texturing units 16 vs the 8800GT's 56

What is the deal with this card it should be running monster numbers?
Really Really bad driver issues?
 

Heyyou27

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The 320 stream processors on a 3870 are not the same as the 112 on an 8800GT. A Geforce 8 series stream processor is quite a bit faster than what ATI calls a stream processor, but that is why they have so many more. I own both the HD3870 and an 8800GTX and while the HD3870 is a fast card, my 8800GTX is quite a bit faster especially with antialiasing enabled at higher resolutions. In general, the 8800GT is faster than the HD3870, although the card is no slouch, and does have Direct X10.1 support, if service pack one ever releases.
 

spaztic7

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The only real benefit for the HD3870 that I have noticed compared to my 8800GTX OC2 is the color is much better with the HD3870. That’s it, oh and all games, the frames rates are hands down in favor of the 8800GTX. (all games that I own)
 

Oh SoS

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the 3870 is going to out perform any other card you can get for under $200.

sure you could spend 3 times that for a GTX, but why?
 

blotch

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From what I read the 3870 has an insane amount of shaders but only a few texture units. The opposite is true for Nvidia's cards. The 3870 is mainly designed for dx10 as it is shader dependent(dx10 means a VISTA ONLY game...a dx9 game with "dx10" add-ins is still primarily using texture fill rate instead of shaders) and the Nvidia cards are designed more for dx9. Also in dx9 AA is done with texture units giving the reason for the 3870s poor handling of current games AA.

There are zero games that are true DX10 games (vista only seeing xp doesnt support dx10...new api and all) and therefore the 3870 and other current ATI cards wont perform up to what they can. Not sure why ATI didnt put a few more texture units in the 3870s so they could compete in dx9 but until a true dx10 game is released Nvidia will outperform ATI in games.
 

nachowarrior

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blotch is correct, more shaders less texturing units comparatively. it has raw power, just not aimed in the current direction, the card will only get better as it matures.
 
Don't forget AA resolve is handled by hardware in the HD series, whereas the GF8-9 series has dedicated hardware, which is fine for titles that do not require the shader based AA which both can do, but on which the HD series relies on for even normal AA.

Even though the HD series may have more potential shader power, alot of it depends on how it's used, and using the shaders is very inefficient if the app doesn't call for or require it.

OP, try a SEARCH next time, already asked already answered many times.
 

SpinachEater

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Yeah but then you won't have drivers to support it. :fou:
 

harly2

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ok, thanks for the feedback, looks like the products from ati and amd seem to be a little ahead of there time recently, thanks.
 

grieve

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do you mean "a little ahead of there time recently" in a good way? Or a bad way? I am thinking bad, but just making sure you think so too. :)