PowerColor HD 4890 1 GB GDDR5

A Closer Look

AMD's HD 4890 cooler is very similar to that of the HD 4870. It uses a copper base plate that is connected to a bigger heatsink via heatpipes. The fan design exhausts hot air outside of the case.


Two six pin power connectors are present on the reference design. Both are required for operation of the card.


The GDDR5 memory chips are made by Qimonda and carry the model number IDGV1G-05A1F1C-40X. With a cycle time of 1.0 ns, they are specified to run at 1000 MHz.


AMD has put two VT1165 voltage controllers on their cards. One is responsible for the VGPU core voltage and the second one controls the memory voltage. This is very nice for overclockers because they can now change both voltages via software. For the average joe, it is a production cost increase that seems quite unnecessary.


This is AMD's new RV790 GPU. It is made in a 55 nm process at TSMC Taiwan with 959 million transistors. Please note that the die size is slightly increased from the RV770, the exact reason for that is unknown.