ATI Radeon HD 4000 Series discussion

[onethreehill]

Radeon HD 4850 Single & Crossfire Quick Test @VR-Zone
http://sg.vr-zone.com/articles/Radeo...Test/5897.html

[spursindonesia]

Aint 4870 not 399$?

Plus the everanoying CF issues. Sometimes you have singlecrad performance, sometimes 10% more, sometimes 50% more etc.

The Racedriver GRID shows it perfectly. Performance is all over the place...pray and roll the random dice.

All this is true for SLI aswell, just in case some fanboys are close to explode in this hyped thread.

HD 4870 for 399 US$ ? Not accoding this leaked slide pic.



Who is the wishful thinker and a shill in this case ?

[Helmore]

uhn this screen confirms R700 = crossfire on one board. (gpu-z shows 4 gpus)

i thought they wouldn't use afr.

There is nothing wrong with AFR, there are however some problems with the way it's currently done and this mainly has to do with the communication between the GPUs en CPU(s). Better communication between the GPUs can probably also help in solving this problem, but my guess is that AFR is here to stay for a while.

[XSAlliN]

As is the picture above 4870 is aimed at 300$ (+/-25$ based on integrator and components used).

[emoners]

was this posted earlier? tried searching but nothing came up... Amazon adds Diamond Radeon HD 4850 to its website



cool looking cooler!

[takamishanoku]

One thing i think gets overlooked is that for CF you need:
- two cards
- a CF mboard
- A very quick CPU not to bottleneck the cards.

So end of the day it may seem cheaper but for the average user who wants great performance CF ends up being the same or slightly more than Nvidia single card.
I won't be getting anything (very happy with my GTX) but just saying.

[zerazax]

Yeah but with the # of Intel chipset users out there, and the fact that the 975X, X38, P45, X48 all support CF and have either x8/x8 or x16/x16 configurations, anyone with a recent motherboard (and P45 will certainly be mainstream) will have CF capabilities, not to mention the 790 lineup for AMD processors.

Nvidia will only have their nForce chipsets for SLI

[perkam]

4870 = $299, and about 20% faster than the 4850 at stock. Ofcourse the real reason for the purchase is two six-pin connectors and no need for the voltmods to reach some nice oc speeds.

The 9800GTX+ vs 4870 should be an interesting battle.

Perkam

[zerazax]

Well if the G92b continues on the G92's tendency to suck at higher resolutions and AA (look at how much the 9800GTX drops in AA in that chart I made compared to the G80 GTX and GTX260), then competing against the 4870 will be no contest once AA and stuff is on

[cadaveca]

One thing i think gets overlooked is that for CF you need:
- two cards
- a CF mboard
- A very quick CPU not to bottleneck the cards.

Jsut an FYI...over 3ghz quad starts to introduce micro-stutter. Having a super-beefy cpu is not really neccesary. In fact it will make your experience worse. Only synthetic benches that actually push cpu requirements need a super-fast cpu. 3DMark vantage easily illustrates this..cpu speed has little effect on 3d scoring.


Now, to correct,

- two cards
- a CF mboard
- a decent cpu with high FSB is required.

[jVIDIA]

No numbers from the 4870 yet ?

[Luka_Aveiro]

Jsut an FYI...over 3ghz quad starts to introduce micro-stutter. Having a super-beefy cpu is not really neccesary. In fact it will make your experience worse.

WTH? Would you mind elaborating that? (I know a more demanding CPU pushes the GFX cards more, but how can it possibly affect framerate O_o)

[Macadamia]

Doesn't that mean a P-P-PPPPPPHENOM is desirable?


D:

[cadaveca]

WTH? Would you mind elaborating that? (I know a more demanding CPU pushes the GFX cards more, but how can it possibly affect framerate O_o)

becuase the cpu goes idle waiting for vgas..this "lapse" while cpu is idle, then loaded, leaves spurts of traffic over the pci-e bus, causing stutter as data from the cpu slows the data flowing in the card out to monitor.


Luka, just check out the slide pics in this very thread about microstutter...it's shown there too.


this is not the only cause of microstutter, but it's definately an issue.



Phenom isn't too bad...it could use 3.2-3.4ghz and a slightly faster bus. Core2 @ 3.0-3.2 400mhz FSB or higher is ideal.



Remember boys, I'ver got dual 3870x2's...I'm dealing with the issue on a daily basis. I've almost completely eliminated the problem...some apps are more prone to it than others though.


It's a problem with memory control...within the vga. vga gets data from cpu, it must buffer the data...no data, it works only on data available, and will use as much of the ringbus as possible.

Cpu sends some data down....it goes on the ringbus too...but now it interferes with rendering as the dispatch controller must deal with pixels in flight, and pixels data incoming.

[jVIDIA]

@ http://forum.donanimhaber.com/m_24110474/tm.htm


512MB of GDDR5 ???! The GDDR5 version of the 4870 shouldn't had 1GB ?

[perkam]

@ http://forum.donanimhaber.com/m_24110474/tm.htm


512MB of GDDR5 ???! The GDDR5 version of the 4870 shouldn't had 1GB ?

Use the Upload, Luke !! Use the upload !!





Pictures courtesy: Donanimhaber

Perkam

[AliG]

not necessarily, that 1gb 4870 was just a rumor, I'm certain that vendors will make it an option though

[Hornet331]

not necessarily, that 1gb 4870 was just a rumor, I'm certain that vendors will make it an option though

they better do this or we see the same thing that happens with the 9800gtx.

[cadaveca]

yeah, I won't buy another vga until i can get 1gb per gpu. 2560x1600 demands it!

[perkam]

they better do this or we see the same thing that happens with the 9800gtx.

Well, the memory hasn't had a significant affect on the benchmarks thus far (20% increase is from 20% core clock increase). I'm assuming the memory speed is bottlenecked somehow, but I have 0 experience in GPU memory bottlenecks and what instigates them

Eeither way, these will fly on LN2, run on air, and make breakfast at stock (Yes these will be hot).

@Cadaveca, there should be 1GB GDDR5 versions out later, and frankly, the GTX 260 not having 1GB does not escape it from the same criticism. I do, however, find your comment a tad juvenile. The increased speed on the GDDR5 modules does help in its ability to process textures faster than GDDR3 at the same memory size. That is why we have memory bandwith, and it does account for something

Perkam

[cadaveca]

Heh, got 30-inch monitor perkam? tried to run AA and AF with 2560x1600...not enough vram to cover all that @ 512mb, plus shader data, etc. lesser res, ok. DirectX tools make it quite apparant how much vram gets used for any app you'd like.


I mean, we could talk about how much mem a single frame of 2560x1600 takes up, vs 1680x1050(2560x1600 takes up 4x+ the data of 1280x800)...512MB is just not enough...it has NOTHING to do with speed, and everything to do with vram size! juvenile, or not, it's the truth!

[perkam]

Heh, got 30-inch monitor perkam?

Got E-peen, Cadaveca ?

When the prices for GDDR5 go down a bit, you will see 1GB cards. You can also crossfire two 4850s if you need 1GB that badly, and most people that have a $1000 to spend on a monitor usually do go xfire and sli, so again, your concern is a tad unfounded.

Perkam

[Hornet331]

Heh, got 30-inch monitor perkam? tried to run AA and AF with 2560x1600...not enough vram to cover all that @ 512mb, plus shader data, etc. lesser res, ok. DirectX tools make it quite apparant how much vram gets used for any app you'd like.


I mean, we could talk about how much mem a single frame of 2560x1600 takes up, vs 1680x1050(2560x1600 takes up 4x+ the data of 1280x800)...512MB is just not enough...it has NOTHING to do with speed, and everything to do with vram size! juvenile, or not, it's the truth!

yup.

just look at the 8800ultra, how it outperforms a 9800gtx, its all in the memory.

also a 260gtx with 896mb (nearly 900mb) should also have enough ram. i dont think 104mb in ram will make a hughe difference.

[STaRGaZeR]

Seriously why people keep comparing and blaming 1GB cards because they get 1 FPS less, it's not about the speed, it's about the size as cadaveca is saying!

[Hornet331]

Got E-peen, Cadaveca ?

When the prices for GDDR5 go down a bit, you will see 1GB cards. You can also crossfire two 4850s if you need 1GB that badly, and most people that have a $1000 to spend on a monitor usually do go xfire and sli, so again, your concern is a tad unfounded.

Perkam

CF dont gives you 1024mb frame buffer, it only gives you 2x512mb. You will experience the same slowdowns when the 512mb are filled.

If CF, only with 2x1024mb pls.