ATI Radeon HD 3870 & 3850: A Return to Competition
by Anand Lal Shimpi & Derek Wilson on November 15, 2007 12:00 AM EST- Posted in
- GPUs
Finally. We're finally getting somewhere interesting in the graphics industry. Although they're sure to return, the days of reviewing $600 graphics card after $600 graphics card are on hiatus, and instead we're reviewing a new class of mainstream cards with earth-shattering performance.
NVIDIA's GeForce 8800 GT kicked off the trend, in one fell swoop making almost all of NVIDIA's product line obsolete thanks to the high performance and low price tag (we'll talk about that last part shortly). But what we saw there wasn't a fluke, it was a preemptive strike against AMD, who have been hard at work on an affordable GPU of their own.
This new product, like the 8800 GT, would be aimed squarely at the $150 - $250 market segment, something both AMD and NVIDIA did a horrible job at with mainstream releases earlier this year (2600 and 8600 both sucked guys).
Introducing the RV670
AMD's two new graphics cards launching today are both based off a new GPU, referred to internally as the RV670. The basic architecture of the hardware is largely unchanged from R600; there has been some additional functionality added, and a great deal of internal bandwidth removed, but other than that this is very much an R600 based part.
The biggest news of this part is that it is fabbed on a 55nm TSMC process. This is a half-node process based on 65nm technology, giving AMD an advantage in die size (cost) and potentially clock speed and/or power.
Historically, AMD's RV series has been a cost cut version of their R series designed for lower end volume parts, and that's where RV670 started. Right of the bat, half the external and internal memory bandwidth of R600 was cut out. External bandwidth dropped from 512-bit to 256-bit, but AMD stuck with 8 memory channels (each dropped from 64bit to 32bit).
Internally, the ring bus dropped from 1024-bit to 512-bit. This cut in bandwidth contributed to a significant drop in transistor count from R600's ~720M. RV670 is made up of 666M transistors, and this includes the addition of UVD hardware, some power saving features, the necessary additions for DX 10.1 and the normal performance tuning we would expect from another iteration of the architecture.
Processing power remains unchanged from the R600; the RV670 features 320 stream processors, 16 texture units and 16 redner back-ends. Clock speeds have gone up slightly and memory speeds have increased tremendously to make up for the narrower memory bus.
The RV670 GPU is also fully PCI Express 2.0 compliant like NVIDIA's G92, the heart and soul of the GeForce 8800 GT.
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Iger - Friday, November 16, 2007 - link
Another interesting question is warranty. Main manufacturers of 8800GT (eVGA and XFX) give lifetime warranty on their products - that's much more impressive than saphire's 1 year...Odeen - Thursday, November 15, 2007 - link
In one word, kinky.Xcom1Cheetah - Thursday, November 15, 2007 - link
At techreport they show that the 3870 power usage under full load is full 39W less than the 8800GT... thats a huge difference..Any idea why there is such a large difference.
http://www.techreport.com/articles.x/13603/9">http://www.techreport.com/articles.x/13603/9
GlassHouse69 - Thursday, November 15, 2007 - link
that makes immensely more sense than the results shown here. the 3850-70 isnt a massive leap and the ram requires alot less juice to run as well. (according to other articles of 3vs4 gddr)just4U - Thursday, November 15, 2007 - link
First off excellent article.As to the sightings .. Ok here in Canada we tend to get things a little later then those in the states BUT the local shop I deal with already has 3850/70s in stock for
179/239 respectively.
For some reason even tho our dollar is finally on par (accually higher then the us greenback) we still seem to be paying higher prices. Perhaps price gouging from the retail stores.. (what ever) But anyhow it's in stock here in Calgary and there's not a 8800GT to be had... which sells at 329(ish) so yeah ... I think ill pick one one up based on this article.
forPPP - Friday, November 16, 2007 - link
You are extremely lucky. In Poland 3870 is listed for $440 !!! OK with VAT (without $360), but it's the same price as for 8800GT. Well, who will buy it then ??? It's a joke - same price, much slower and more power hungry ! ATI what happened !?
just4U - Thursday, November 15, 2007 - link
mmm ok so I was wrong. Shops around here have them listed but don't yet have them in stock. They are expected over the next few days.falacy - Thursday, November 15, 2007 - link
This is something we should all keep in mind, given that nothing has fundimentally changed in PC computing in the last 8 years. There is still a lot of fun to be had from the plethora of older PC games, which even the lowest end harware can play in full detail (with the exception of Unreal, which really taxes older hardware). And hey, if you're not going to complain about waiting 10 seocnds for it load, Open Office works great on lowend hardware too. Heck, even the lowest end Conroe CPUs trounce the 3.0GHz Pentium4 line in video tanscoding (and it would be interesting to see how the new Celeron 4xx series stacks up against a Pentium4 with 512K of chache, as they are both single core...).I just purchased a EVGA E-GEFORCE 8600GT Superclocked 567MHZ 256MB 1.5GHZ GDDR3 PCI-E Dual DVI-I HDTV Out Video Card for $95 CAD, which sure beats the $110 CAD that the 8500GT was priced at a couple of weeks ago. As far as usefullness goes in the $100 price segment, the 8600GT is a great buy, as it has playable graphics at 1280x1024 and 1024x768 in many games, where the 8500GT just does not.
Hopefully now the passively cooled 8500GT models, which have smaller heatsinks and price tags than the passively cooled 8600GT, will be the standard for HD player PCs and we can all forget about the 8400 line of cards.
It would have been nice to get one of the 3850s, but for the extra $80 it's not really worth the performance boost for people like me who are still using a 1024x768 CRT and Windows XP, playing older games and who perhaps have gotten too old to want to chase the latest gaming craze. I do have the hardware for Vista 64bit, but it's not worth hassle of the side-grade, when there isn't anything out there I feel compelled to play in DirectX 10. Maybe in a couple years there will be more DX10 titles that it will be worth upgrading the OS and monitor, rather than spending money on hardware.
I'm running an ASUS P5K-VM, Pentium-Dual Core E2160, 1GB DDR2 667, which leaves my Pentium4 531 and 1GB DDR in the dust! Apart from only supporting PCI-E 1, this board will stand the test of time, so long as games/applications become more quad-core optimized, but for right now it's a super fast, super cheap computer compaired to what I paid for my Celeron 300a based uber-computer I had less than 10 years ago!
poeticmoons - Thursday, November 15, 2007 - link
It’s seems like you just ran over the fact that the 3870 is a dual slot card. Now I know that the 8800GTS and GTX were dual slot, but the 8800GT isn’t and I feel that is a very important factor. I don’t see how you would run 4 dual slot GPU’s in an ATX form factor case. Yes I know that the 3850 is a single slot card, but the high memory GT isn’t competing with that card it’s competing with the 3870. With a die shrink I would have just assumed that a dual slot card would be unnecessary.Spoelie - Thursday, November 15, 2007 - link
Text hints at 3870 actually being quieter, while the slide mentions otherwise. Any data to back this up? Also, is the quieter part during idle or load, or both?