We used to say that multi-GPU solutions, especially discrete ones, were limited to expensive and luxurious computers of enthusiasts who did not care about money when it came to ensuring maximum performance. Even if not worse in terms of sheer speed, entry-level multi-GPU solutions used to be inferior to single-GPU cards in such consumer properties as reliability, compatibility, ease of use, etc.
Still, multi-GPU technologies have been evolving and getting rid of their downsides. And we can now say that they have matured for real, especially in the hands of AMD/ATI specialists. Their Radeon HD 4870 X2, based on two rather simple and inexpensive RV770 GPUs, has enjoyed a long period of being the fastest single-PCB graphics solution, beating the best single-chip products Nvidia could offer.
CrossFireX technology has not been that successful in the lower market sectors, though. For example, the Radeon HD 4850 X2, a less advanced counterpart of ATI’s flagship model, has not been recognized by ATI’s manufacturing partners and is so far represented with only one product on the market (it is the Sapphire HD 4850 X2 2G/1G GDDR3 and you can read about it in our earlier review). Users’ demands seem to be fully satisfied with classic single-chip graphics cards in the lower price segments although there is a niche for multi-GPU technologies there, too. As we showed in our earlier article, a pair of Radeon HD 4830 cards cost less than one Radeon HD 4870 but delivered higher performance (and offered an inexpensive way of upgrading the graphics subsystem for people who had one Radeon HD 4830).
Considering the recent reduction of prices on AMD/ATI’s produces, we are interested to learn how appealing an even cheaper CrossFireX subsystem, based of two Radeon HD 4670 cards, may be. This simple affordable RV730-based graphics card is a perfect choice for HTPCs but is no good for gamers due to its low performance in modern games – it has only 8 raster back-ends and a 128-bit memory bus. The new recommended price of the Radeon HD 4870 is only $149 (for the version with 512 megabytes of memory) and buying two Radeon HD 4670 cards at once won’t be much of a saving. But is there an option of cheap upgrade if you’ve already got one such card? Let’s see how effective this anti-crisis solution is from a technical point of view.