I know the 4870x2 isn't out yet but i've heard it will help with scale 15% better than two 4870's in xfire, however, does anyone know how it would scale with another 4870? The 4870 i'm planning on buying is 512mb while i believe the 4870x2 is suppose to have 2GB of memory, would the 4870 bottleneck the x2 and lower its memory use to only 512mb? I saw something about that in the SLI faq and i'm somewhat worried right now becuase i want to play all the newest games on 1900x1200 res with max settings and all eye candy turned on. Yes i know the 4870x2 isn't release but does anyone have articles describing how it would scale when it comes out paired with a 4870 that is currently out?
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  1. The 4870x2 is basically 2 4870's thrown into 1 card, due to how it is setup supposeably the it will read and act as 1 single card and not 2 as if it were in crossfile in a single PCI E, so it will have 1gb of memory total, which will actually act as a true 1gb of memory. So I doubt you could toss it in crossfire with a single 4870 card.

    Sorry if what I wrote was confusing but it's because I don't fully understand how it works. You should head over to the graphics and display forum to get a better idea of what it is, there are several threads on this card.
  2. Mmmmm.....As far as I know if this latest series of ATI cards are anything like the 3850, 3870 and 3870x2 you will be able to run a 4870x2 with another 4870 in the second slot. There aren't any tests out to confirm this for sure yet, but the previous generation was certainly capable. Scaling was very good with 2 GPU's (on average), but scaling was probably in the 40-70% range of the scaling seen going from one GPU to two when the third GPU was added, and then became almost non existent with the fourth GPU. You can search this out yourself....which might be a good idea, since I am working from memory...out of a 51 year old brain :-)

    Also, the 3850's, 3870's single and dual core can be mixed and matched with the latest generation cards in Crossfire configurations.

    the canuck
  3. wait you can add like a a 3850 to a 4850? and crossfire them?
  4. Yup! You can. That is the best news from Xfire, unlike SLI. Altough the result from combining HD3850 and HD4850 will weaker than from 2xHD4850.
  5. Please correct me when I am wrong 'bout HD4850 and HD3850.
    I have Xfired X1650XT with a X1950pro, and it worked. So I just assume that SLI can be achieved by combining 2 different GPUs.
  6. random_2 said:
    Also, the 3850's, 3870's single and dual core can be mixed and matched with the latest generation cards in Crossfire configurations.
    Im not so sure you can do that. I think ATI figured out if they enabled that option they'd sell a lot less video cards?
  7. Author Icon

    Posts: 469
    Joined: 02/19/2008

    It used to be possible, from what I hear, but the ATI support team apparently decided there are compatiblity issues and the latest drivers make it impossible.

    However... The 4870 is at the very least twice as powerful as the 3870, mind you. Just about every review I've seen that pit the 4870 against any dual-3870 setup (3870X2 and two 3870s crossfired) has shown the 4870 ahead of the crossfired 'older generation'.

    It's also a new card so every new driver version is likely to increase performance more greatly than it would with older cards.

    Hope this information helps you in your choice of upgrade.

    Me? I've already ordered an Asus-brand EAH4870 to replace my EAH3870X2. The X2 is going into another system that will go to someone in my family.


    This is out of the FAQ from the ATI site. Well there you have it....Thought I had heard this was possible! No longer the case though.
  8. Here's another spin on this from TG Daily. Kinda interesting!!! :-)

    ATI Radeon 4850/4870 mix and match with Radeon 3850/3870 PDF Print E-mail
    By Theo Valich
    Monday, June 23, 2008 00:01
    Mountain House (CA) %u2013 If everything goes according to plan, we will see AMD%u2019s new Radeon GPU launch this week. But there is more news to this announcement and we are thinking about one special item you are unlikely to hear about: During AMD's Cinema 2.0 schmoozapalooza in The Americano restaurant in San Francisco we learned that your Radeon 3850, 3870 or 3870 X2 graphics card will hold extra value: Don%u2019t get rid of your old card just yet.

    A source close to AMD told us that there will be %u201Cinter-generation compatibility%u201D between the Radeon 3800 and 4850: %u201CSince they're both DirectX 10.1 parts, there is no reason why those two should not work together. (%u2026) We will probably not qualify this interoperability, but who stops you from trying?"

    It appears that ATI did not integrate a driver lock or something else that would stop you from combining a 3870 card with a 4850 or with a 4870 model. Just keep in mind that these two cards need to include the same amount of memory. If you mix and match a 3850 with 256 MB of memory with a 4850 512 MB, the 4850 card will default to 256 MB. If you wonder whether you will be able to combine a 3870 X2 card with a 4850 board, our sources indicated that this scenario should work as well.

    There is nothing not to like about this interoperability. I personally believe this is a big win for the consumer: How often do you have to throw you old card away when a new generation is introduced? Usually, always (well, at least, if you are among those who try to always have the latest and greatest.)

    Here's the link: http://www.tgdaily.com/content/view/38056/135/

    An older article from Legit Reviews mixing 3870 and 3850: http://www.legitreviews.com/article/663/1/
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