why is 8x agp worthless??

[jjyiz28]

something about not using all the bandwidth? 8x supporting 2.1gb/sec. but what if you have a 64mb video card 8x agp, when a game uses up all the 64 mb, it uses some system memory, so then won't 8x be a lot more beneficial over 4x?

 

[Naruto]

0 fps increase, thats why its somewhat useless. All vga cards cannot handle enough bandwith to exceed 4x, so why does it need 8x.

 

[Fallen Kell]

When most video cards already have 128 megs of ram on board...what is the need for more bandwidth to system ram? Seriously, the idea behind AGP was to allow for the graphics cards to use the system ram, but now the graphics cards easily have more ram then what the systems had back when the AGP spec was created.

 

[jjyiz28]

i see, so in all honesty, having a 1x agp card will have no performance penalty as long as it has 128mb onboard ram?

also, what is the benefits of 8x if you have onboard video card which uses shared memory from your system memory?? then a 8x agp will benefit over 4x right?

 

[sandorski]

It's not worthless, but it's not worth more either.

 

[boyRacer]

well as of right now there's no use for it really... i wouldn't call it completely worthless... it's there to prevent the AGP being the bottleneck if ever we come to the point that 4x can no longer provide the required bandwidth... but that's a long way to go still. plus it looks good when your motherboard can advertise that it supports the latest and the greatest...AGP 8X

 

[eklass]

if you've not maxed out 4x, what's the point in 8x ?

answer: marketing

 

[Batman5177]

8x is a total marketing scheme!!!

 

[CraigRT]

Originally posted by: Batman5177
8x is a total marketing scheme!!!

yes, it does nothing for you.

agp 8x is a total scam really

 

[jjyiz28]

you guys really didn't answer my question. what do you mean we didn't max out 4x yet?? did we max out 2x agp then?? do you mean the bandwidth of agp is not only for use for getting memory out of your system ram but for something else too?? i asked WHY its worthless. ok, it doesn't need the 2.1 gb/sec 8x agp, but WHY? is it because video cards are not transfering data close to 2.1gb/sec to your system?? i kknwo its a marketing scheme, but WHY WHYWHWYW is it not needed?? gimme some technical data.

 

[Marshallj]

Originally posted by: jjyiz28
something about not using all the bandwidth? 8x supporting 2.1gb/sec. but what if you have a 64mb video card 8x agp, when a game uses up all the 64 mb, it uses some system memory, so then won't 8x be a lot more beneficial over 4x?

And in MS Windows, when your computer uses up all of its ram, it uses the HD as memory. Same principle. You have a fast form of memory storage, and once it gets used up the PC reverts to a much slower form of storage. Your HD is nowhere near as fast as RAM, and using the 2.1 GB/s AGP bus for texture memory is nowhere near as fast as the 10GB+/s memory bus that's on your video card.

Once you're forced to switch to a slower data transfer medium, you're going to take a performance hit.

 

[jjyiz28]

Originally posted by: Marshallj

Originally posted by: jjyiz28
something about not using all the bandwidth? 8x supporting 2.1gb/sec. but what if you have a 64mb video card 8x agp, when a game uses up all the 64 mb, it uses some system memory, so then won't 8x be a lot more beneficial over 4x?

And in MS Windows, when your computer uses up all of its ram, it uses the HD as memory. Same principle. You have a fast form of memory storage, and once it gets used up the PC reverts to a much slower form of storage. Your HD is nowhere near as fast as RAM, and using the 2.1 GB/s AGP bus for texture memory is nowhere near as fast as the 10GB+/s memory bus that's on your video card.

Once you're forced to switch to a slower data transfer medium, you're going to take a performance hit.

thank you , thats the kind of info i needed. so i take it there will not be any performance increase at all if the card is 128mb memory, since most games don't use up all that memory. but you DO get performance increase with say a 32mb card with hypothetically 8x agp even though the performance may be very small. is what i said correct? also, slightly off tangent, i read that pci-x will replace agp and will support bandwidth several several times more than agp now, so will that mean that it will finally mean that video cards will have no use with memory onboard but using the pci-x interface it will be more than plenty faster supporting up to or even more than 10 or even 20gb/sec??

some more questions. a card has a 128bit interface, therefore it equals 16 bytes, memory is clocked at 325 and since it is ddr memory it is 650mhz. therefore, 16 bytes multiply by 650 mhz is 10400mb/sec or 10.4gb/sec. is this correct??

ok, so why is everyone saying that we are not at the stage of using up the bandwidth of 8x agp(2.1gb/sec) or even 4x agp(1gb/sec)???? this doesn't make sense to me since 8x isn't even close to the 10gb+/sec.

 

[BenSkywalker]

thank you , thats the kind of info i needed. so i take it there will not be any performance increase at all if the card is 128mb memory, since most games don't use up all that memory. but you DO get performance increase with say a 32mb card with hypothetically 8x agp even though the performance may be very small. is what i said correct?

Mostly, under some very narrow circumstances AGP 8X can provide a benefit, but not much and not something you are likely to notice.

so will that mean that it will finally mean that video cards will have no use with memory onboard but using the pci-x interface it will be more than plenty faster supporting up to or even more than 10 or even 20gb/sec??

There are already vid cards with bandwith in excess of 20GB/sec, by the time AGP is replaced that number could be doubled or trippled.

some more questions. a card has a 128bit interface, therefore it equals 16 bytes, memory is clocked at 325 and since it is ddr memory it is 650mhz. therefore, 16 bytes multiply by 650 mhz is 10400mb/sec or 10.4gb/sec. is this correct??

To move from Bytes to KiloBytes to MegaBytes, etc, you need to divide by 1024, not 1000. Your calcs work out to 9918MB/sec or 9.686GB/sec.

ok, so why is everyone saying that we are not at the stage of using up the bandwidth of 8x agp(2.1gb/sec) or even 4x agp(1gb/sec)???? this doesn't make sense to me since 8x isn't even close to the 10gb+/sec.

AGP is useful for more then just AGP texturing. All the objects you see in a game must be uploaded to your graphics card first. AGP texturing is handy when at a given point you are exceeding the on board RAM, higher levels of AGP bandwith allow you to send more vertex data, shader programs etc to the vid card at once. Right now, bandwith for these types of operations isn't needed, but at some point it will be ignoring AGP texturing completely. For these functions, you could have a 10GB vid card and it still would be a bottleneck at some point(although this data can be cached on the vid card, it still needs to be uploaded in the first place).

 

[jjyiz28]

Originally posted by: BenSkywalker

AGP is useful for more then just AGP texturing. All the objects you see in a game must be uploaded to your graphics card first. AGP texturing is handy when at a given point you are exceeding the on board RAM, higher levels of AGP bandwith allow you to send more vertex data, shader programs etc to the vid card at once. Right now, bandwith for these types of operations isn't needed, but at some point it will be ignoring AGP texturing completely. For these functions, you could have a 10GB vid card and it still would be a bottleneck at some point(although this data can be cached on the vid card, it still needs to be uploaded in the first place).[/

thanks for all your answers so far ben. ok, now this makes sense. so agp 8x isn't needed two fold since 1, agp texturing wont be used at all if you use a 128mb memory card which is enough for games for the moment, and 2, gettting data TO the card itself, the bandwidth is not close to being saturated. ok . i think i get it now. i learned a lot. thanks ben. =)

 

[Atekk313]

well all this technical mumbo jumbo makes my head spin.. but i would have to agree from the benchmarks ive seen all over forums online.. the average FPS increase on a AGP 8x mobo is an average of 3-7 FPS..not a big increase at all... and if u think about it the increase in FPS isnt even due to the AGP 8x spec, i would think the increase comes from the newer age chipsets (this assumption is made based on the fact that the FPS increase is still gained WITHOUT a new video card purchase)

Any Objections?.. or are we all in agreeance?

 

[Regs]

Well there has to be a difference between AGP 1x and 4x. If there was not then all we would have to do is buy a cheap PCI graphics card. Does the information get transfered faster on a AGP bus then a PCI bus? I know this is besides the point, but I'm now dieing to know.

 

[Smilin]

There was a HUGE jump from 1x to 2x and then a minimal one from 2 to 4. 4x to 8x is mostly wasted. It will be a great benifit once the polygon count starts jumping through the roof but for now it's mostly a waste.

The simplest answer why 8x is not much better than 4x:
Because if your video card doesn't have enough texture memory to hold everything at once it will have to read across the AGP bus. If this happens it doesn't really matter if you are at 16x...it won't be fast enough and you're going to texture thrash.

 

[Marshallj]

Originally posted by: Regs
Well there has to be a difference between AGP 1x and 4x. If there was not then all we would have to do is buy a cheap PCI graphics card. Does the information get transfered faster on a AGP bus then a PCI bus? I know this is besides the point, but I'm now dieing to know.

This was already explained on this thread.

 

[BFG10K]

AGP x8 isn't useless, it's just not needed right now. Of course it's a natural progression from AGP x4 and like all things similar, it will show benefits later down the road. There is a big difference between AGP x1 and AGP x4, for example.

Also AGP is used for much more than just simple AGP texturing as it transfers all of the data required for 3D scene (pixel/vertex shaders, geometry data, etc). Not all of it is done constantly and in realtime but the bottom line is that you want the pipe to be as fast as possible as when it does need to transfer something it'll be faster.

And no matter how much VRAM your card has, you'll always need to use AGP to transfer at least some data in realtime.

 

[touchmyichi]

You actually get a little preformance increase. Its so easy for mobo makers to implement, so they might as well put it on.