PCB Design and Specifications
The Palit website says that the described graphics card exists in two variants: one is a copy of the reference card from Nvidia and another has a unique PCB and cooler. Palit Microsystems has enough R&D resources to indulge itself in risky experiments with top-end graphics card designs such as Nvidia GeForce GTX 470/480 or ATI Radeon HD 5970. We’ve got the second variant of the card, which is the first nonstandard GeForce GTX 470 ever to be tested in our labs.
The new card is a very interesting sight. It is shorter than the reference model at 22.8 centimeters as opposed to the reference card’s 24 centimeters. The difference may seem negligible, yet even one or two centimeters may be crucial for whether the graphics card fits into the particular system case or not. The shorter length is due to the lack of vent holes in the PCB. You can see that clearly when the cooler is removed:
The component density is higher than on the reference card. The PCB might have been made even shorter if Palit used integrated power modules, but this would also have made the card more expensive to manufacture. Therefore we do not blame Palit for using large power transistors. The developers of this GeForce GTX 470 have done a good job anyway.
The GPU voltage regulator has four phases and is managed by an NCP5392 controller from ON Semiconductor. The power circuit allows to install an 8-pin PCIe 2.0 connector, too. We won’t be surprised to see Palit use this PCB for pre-overclocked versions of the GeForce GTX 470.
A Richtek RT9259 is responsible for powering the memory chips.
Like the reference GTX 470, this card is equipped with Samsung K4G10325FE-HC05 memory. The ten such chips on board the Palit card make up a 1280-megabyte memory bank accessed across a 320-bit bus. Like the reference card’s, the memory frequency is 837 (3348) MHz, delivering a peak bandwidth of 133.9 GBps. The Palit card lowers its memory frequency 67 (270) MHz in power-saving modes.
The GPU has the same marking and revision number as the one of our reference GeForce GTX 470. It was manufactured on the 16th week of 2010. The clock rates are the same as those of the reference card: 608 MHz for the main domain and 1215 MHz for the shader domain. The GPU configuration is standard with 448 stream processors, 56 TMUs and 40 RBEs. In the card’s first power-saving mode the GPU clock rates are dropped to 405/810 MHz. This mode is used for such tasks as hardware video decoding which do not call for all GPU resources. In the second mode the GPU clock rates are lowered to 51/101 MHz so that the card could save a lot of power when running 2D applications. We call this Desktop mode. The default GPU voltage is standard at 0.987 volts. It is lowered to 0.875 volts in the power-saving modes. The GPU voltage can be controlled via MSI Afterburner but we wouldn’t recommend to volt-mod the card even with software tools because, if applied indiscreetly, this may damage it. Hardcore overclockers can hardly be stopped by our warnings, though.
The Palit GeForce GTX 470 has the following connectors:
Instead of the reference card’s unhandy mini-HDMI connector which requires an adapter, the Palit GeForce GTX 470 offers a full-size HDMI port. It features an individual DisplayPort as well. For all this abundance of interfaces, you can only use more than two displays simultaneously if you enable SLI mode. The card has two standard MIO connectors to support SLI. To build a SLI configuration out of our Palit GeForce GTX 470 and Gigabyte GeForce GTX 470 cards we only had to connect them with a bridge and enable the appropriate option in the Nvidia control panel.
The cooling system has nothing to do with the reference cooler. The casing with two 80mm fans covers a low-profile long heatsink connected to the copper base with three heat pipes.
The heatsink is cooled by a couple of 4.2W fans from Power Logic (PLA08015B12HH, 39 CFM). Judging by the marking, the fans run on fluid dynamic bearings.
The base that the heat-exchanger and heatsink reside on is made from aluminum and takes heat off the memory chips and power circuit components through elastic thermal pads. There is a layer of dark-gray thermal grease between the heat-exchanger and GPU cap. We replaced it with our own KPT-8 when we took the card apart to put it back together. On the whole, the cooling system installed on the Palit GeForce GTX 470 looks more clever and effective than the reference one. The single downside is that some of the hot air returns back into the system case, yet this shouldn’t be a problem for a well-ventilated computer. We will check out the practical efficiency of this cooler in the next section.