If you haven’t already seen them, there are a couple of reports around the web with some mixed information about the R700 series from AMD. It’s now certain that the cards will be called Radeon HD 4000, and the first card will be Radeon HD 4850 on June 18th, and don’t worry too much about the availability, it’s a hard launch. It will be followed by the Radeon HD 4870 one week later, but the availability will be a problem because there aren’t enough GDDR5 chips yet.
This is also the reason the launch was postponed from late March, that and the fact that AMD wanted the cards to arrive closer together. The bad part about this is that NVIDIA will release its GT200 before AMD releases the Radeon HD 4800 series.
We don’t expect the Radeon cards to be able to keep up with NVIDIA’s counter-part, but then you have to remember that GT200 is a high-end chip, while RV770 is mid-range. Two RV770 chips will be paired together to make Radeon HD 4870X2, which is high-end and intended to compete with GT200.
Radeon HD 4850 will use 512MB or 256MB GDDR3 memory, single-slot cooler, a single 6-pin PCIe power connector and a core clock similar to that of Radeon HD 3850. The exact frequency will not be revealed by us. Power efficiency is a key element for AMD, and this is one of the main reasons the core clocks are held back. PowerPlay is even more intricate now and will keep the temperatures and power drainage at a minimum.
Previous reports found elsewhere have stated that Radeon HD 4870 will come with a core frequency above 1GHz, the first graphics card to do so, but that’s not true, it never was. It’s more in line with Radeon HD 3870. The memory will be GDDR5 runnings at sub-4GHz frequency, and cooler will be dual-slot, not so much because it needs it, but because AMD wants to leave room for overclocking as the core as the reference clock is a bit too low for some people.
The last card of the Radeon HD 4800 series is the high-end Radeon HD 4870X2. Like the HD 4870, it will use 512MB GDDR5 with each core, but it doesn’t seem like we’re getting the shared memory buffer we were hoping for. The PCB and bridging of the RV770 cores have been improved significantly though, but we’re not sure how much performance the card will gain from this.
Some of the more optimistic sources says that Radeon HD 4870 will perform like Radeon HD 3870X2, but this was mainly suppose to be because 3870X2 is an underperformer. There is also a mention of a physics support that puzzles us. AMD has scrapped its in-house physics as far as we know, and it may in fact be support for “PhysX” AMD is talking about.
The Universal Video Decoder has been upgraded to version 2.0 and the lower-end Radeon HD 4000 series card, will become a hot alternative among HTPC users. These won’t arrive until later on in Q3. Previous stories have stated these cards will not be the same low-end disappointments the Radeon HD 3600/3400 series were. We have no real evidence to back these claims up at this time.
As we’ve said so many times before, the Radeon HD 4000 series will slide in and replace the Radeon HD 3000 series at equivalent prices. Expect aggressive prices and plenty of overclocked cards from partners. CrossFire performance is suppose to be even better now thanks to core optimizations and “new technology.” Which also falls in line with AMD’s new approach of just making mid-range cores and then you have to pair them together to get more performance frames per second.
The die size of RV700 is about 35% larger than RV670, 256mm² vs. 190mm², which means that the number of transistors should is around 900 million, but can be even more since we know TMSC has a new and more efficient 55nm process in action. We still stand by the western stories that RV770 has 480 shader processors, and not 800 like the eastern rumor mill says. Both mills agree on 32 TMUs though.
