AMD today announced the Radeon HD 4870 X2 graphics card, which shouldn’t catch any of our readers off guard since we have already published a preview on a prototype card. The Radeon HD 4870 X2 is basically two ATI Radeon HD 4870 series GPUs with a more advanced cross-GPU connection based on the PCIe 2.0 standard, plus two gigabytes of GDDR5 memory on a single printed circuit board (PCB).
With 2.4 teraFLOPS of graphics horse power, 1600 stream processors and 2GB of GDDR5 memory on a 256-bit bus this might be the fastest and most powerful graphics card available if it does well in the benchmarks. With 956 million transistors per core these are the real deal! The ATI Radeon HD 4870 X2 is immediately available from e-tailers worldwide priced at USD $549 MSRP.
The just released Radeon HD 4870 X2 graphics card has the exact same features as the Radeon HD 4870; just has twice as much everything as you can see from the feature chart above.
Like I mentioned in our preview on the Radeon HD 4870 X2, the card has an improved PCI Express 2.0 bridge chip and has a total interconnect bandwidth of 21.8GB/Sec. The old Radeon HD 3870 X2 had a total interconnect bandwidth of just 6.8GB/Sec, so this is a huge improvement. You might notice that the Radeon HD 4870 X2 has something called sideport for direct connection between the GPUs. This feature is in the hardware, but is not enabled via software as it is not needed right now. AMD informed us that when future games come out that they could enabled sideport through a driver update to improve performance. We contacted AMD to get a comment on this ‘mystery’ feature and were given this statement to pass along to our readers:
The sideport is an advanced interconnect technology introduced in the ATI Radeon HD 4870 X2 to deliver additional bandwidth if and when needed. To date, the improved Gen 2 PCI Express bridge in the ATI Radeon HD 4870 X2 has provided more than enough interconnect bandwidth without use of the sideport, however its inclusion does provide headroom for future applications.
If the ATI Radeon HD 4870 X2 is out of your price range then the upcoming Radeon HD 4850 X2 graphics card might be worth the wait. The ATI Radeon HD 4850 X2 is scheduled to be available in September at an estimated price of USD $399. What is this a Radeon HD 4850 X2 graphics card? Basically, the Radeon HD 4850 X2 is two Radeon HD 4850 cores on one PCB. The performance will be lower than that of the Radeon HD 4870 X2, but it should offer a great price versus performance value when it arrives next month.