|MSI N460GTX HAWK GeForce GTX 460|
|Reviews - Featured Reviews: Video Cards|
|Written by Bruce Normann|
|Friday, 24 September 2010|
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Closer Look: MSI N460GTX HAWK
The MSI N460GTX HAWK is a full-out assault on the NVIDIA GF104 GPU. As I mentioned in the Features section, the N460GTX HAWK distinguishes itself from the reference cards based on three major areas: improved cooling, Military Class components, and overclocking capability. We're going to take a closer look at what MSI has accomplished here, and then dive into more detail in the next section.
The first thing you notice with this video card is the dense construction of the heatsink fin assembly and the twin fans. The two fans are the same size as the single unit on the NVIDIA reference design, but as used here, they push twice as much air through the aluminum fins. (Note: This is never the case when two fans are used in a push-pull arrangement, which is popular on some CPU coolers.) It's a given that increasing clock speed and voltage for any GPU will increase heat generation within the chip, which has to be removed. So, if you're going to release a graphics card that is just begging to be overvolted and overclocked, it's a wise idea to bump up the cooling capacity, as well. The fan upgrade is an obvious enhancement, and it‘s worth taking a good look around to see how they are integrated into the overall cooling system.
The fan shroud isn't a sealed-off design, by any stretch of the imagination. Most of air flows out the perimeter of the card, after it passes by the memory chips, the voltage regulator modules and other power supply components. After the GPU itself, these are the things that benefit the most from active cooling. My experience with GDDR5 memory so far, is that it runs awfully cool all by itself, and it doesn't need or benefit from additional cooling. That being said, the two fans do blow a good portion of air down in the direction of the eight DRAM chips arrayed around the perimeter of the GPU. The fans are devoid of any logo and are eleven-blade designs that sit just a bit higher than the edges of the shroud. They are PWM controlled designs, and the board supports the required 4-wire electrical connection. A single fan provides the PWM and tachometer signals back to the fan controller, so as not to confuse it with two sets of feedback signals.
The power section features a dense array of state-of-the-art components: solid polymer capacitors, solid construction of both the smaller surface-mounted chokes and the ferrite units at the output of the PWM controlled MOSFETS. The VRM implementation is a true six-phase design and uses discrete MOSFETs for Low side and High side positions. The drivers are on the back side of the board, and we'll look at them next. The DRAM power section on the left uses a similar discrete design, but only a single phase driven by its own independent controller. You can also see the voltage monitoring test point connectors at the top of the photo.
On the back side of the board are the main PWM controller and the three two-phase driver ICs that power the six independent phases on the top side of the board. These particular driver chips, from uPI Semiconductor feature a "Phase Extension" feature, which takes the three phase output of the main PWM controller and divides it up into the six separate phases. Don't be fooled into thinking that the board only has three phase power going to the GPU.
There are no open-frame power supply chokes in this design, so that source of high pitched noise has been eliminated at the source. The board is fed from two 6-pin PCI-E power connectors exiting the rear of the fairly short card. There should be no problems fitting this card, and its connectors, in any standard ATX style chassis. The 6-pin PCI-E connection is highly underrated, at 75W each. The real capacity of a 6-pin connector is at least 100W, so there is approximately 275 W available from the standard connector arrangement (including the X16 PCI Express connector on the motherboard), well above the card's rated 160W maximum requirement. Once again, you can see the voltage monitoring test points, just to the left of the power connections. You can also see the limited clearance between the aluminum fin assembly and the taller components on the board. MSI packed as much cooler as they possibly could into this dual-slot envelope.
The PC board had excellent solder quality and precise component placement, as can be seen here. The component placement is quite good; this is the area on the back side of the board, directly below the GPU, and is one of the most crowded sections. On my LCD screen, this image is magnified 20X, compared to what the naked eye sees. The small SMD resistors located side-by-side in this view are placed on 1mm centers. This is one of the most critical sections of the PCB for build quality, as variations in stray capacitance here could impact the performance of the GPU, and certainly its overclocking ability.
This board was unfortunately not any cleaner than some of the rougher samples I've looked at recently. There were significant traces of residue across the whole surface of the board. Once you start looking at macro photographs like this, there's no place for any manufacturing shortcuts to hide. All manufacturers are under intense pressure to minimize the environmental impact of their operations, and cleaning processes have historically produced some of the most toxic industrial waste streams. The combination of eco-friendly solvents, lead-free solder, and smaller SMD components have made cleaning of electronic assemblies much more difficult than it used to be. You can take some solace in the fact that the environmental cost to produce this board was less than one that is sparkling clean.
The layout on the front and back of the printed circuit board is similar to the NVIDIA reference card, with the exception of the power supply design. It's still a fairly simple design, and there are fewer components mounted on the back side than on a full-bore high end card. The GPU cooler is mounted with four spring-loaded screws, without the aid of a skeleton back plate. There are no additional cooling considerations for any of the power supply components or the GDDR5 RAM chips. However, all of them benefit from the direct airflow of the two cooling fans.
This new card is still a relatively simple design, even with the additional power supply components, yet it dares to compete with some pretty sophisticated Cypress and Fermi-based products. The test results will show that very clearly. It's relatively compact, runs cool and doesn't use as much power as its direct ATI competitors. It's all down to the design of the GF104 GPU really, which comes as somewhat of a relief. After the first round of nuclear powered GF100-based cards came out, I was wondering if NVIDIA had completely lost the bubble. Now I know they haven't.
Let's take a more detailed look at some of the new components on this non-reference board. I did a full tear-down, so we could see everything there is to see...