 |
|||||||||||
|
|
|
|||||
The HIS Radeon HD 4890 iCooler x4 (1GB) is a serious looking graphics card, largely due to the massive heatsink. However the card itself is actually built to the AMD specification, measuring 24cm long. This makes this graphics card just as long as your typical Radeon HD 4890 or even Radeon HD 4870.  Like the AMD reference Radeon HD 4870 graphics cards, this HIS version features a dual slot cooler, though the design has been improved. The heatsink found on the HIS Radeon HD 4890 iCooler x4 is bigger, while also featuring not two but rather four copper heatpipes, which help improve cooling by moving heat away from the heatsink base more efficiently.   The fan used measures 70mm in diameter and is of the traditional 2-ball bearing design, where as the reference cards use a blower type fan, which generates significantly more noise. Like the reference card the Radeon HD 4890 iCooler x4 does feature an exhaust system that pushes the hot air out of the case, though not all the hot air escapes out through the rear of the case.   The heatsink measures 18.5cm long, 7cm wide, and at its thickest 2cm, so it is really quite a large heatsink. HIS has also designed a fan shroud that is designed to direct more air-flow over the heatsink. Improving efficiency are four heatpipes that extract heat from the base plate directing it through the row of fins, and as you will find later on in the review, this setup works rather well.  Like the Radeon HD 4870, the newer HD 4890 uses a 55nm design. However in the 10 months that have passed since the release of the Radeon HD 4870, ATI has had time to perfect the process. The more capable RV790 XT core runs at 850MHz, while the older RV770 XT GPU featured on the Radeon HD 4870 operates at just 750MHz.  HIS is shipping their Radeon HD 4890 iCooler x4 (1GB) with Qimonda ICs on-board (IDGV1G-05A1F1C-40X). These GDDR5 modules are already rated for 4.0GHz operation, so we don't expect to be able to push them much further. Interestingly, HIS has not decided to cool the graphics cards onboard memory chips, leaving them completely naked.    Other than the improved cooling solution, the only other major modification to the Radeon HD 4890 iCooler x4 is the power delivery system. The power circuitry of this new HIS graphics card is nothing like that of the ATI Radeon HD 4890 reference card. This new design is intended to deliver even more power to the GPU when overclocking. In order to do that the design ditches the dual 6-pin PCIe power connectors for a 6-pin and 8-pin configuration.   Another interesting feature of the Radeon HD 4890 iCooler x4 graphics card is its I/O capabilities. This card is equipped with HDMI, which is impressive, though HIS has also opted to include an old VGA port. The inclusion of the VGA port has us a bit miffed, as HIS could have provided a pair of DVI ports instead and gone with a DVI to VGA adapter for legacy support. |
|||||
|