|XFX Radeon HD5830 DX11 Video Card|
|Reviews - Featured Reviews: Video Cards|
|Written by Bruce Normann|
|Friday, 26 March 2010|
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Closer Look: XFX Radeon HD 5830
The XFX Radeon HD 5830 is definitely a full member of the 58xx family; the GPU is not some sort of hybrid between Cypress and Juniper. The one thing that might lead you to think that is the GPU cooler that XFX has chosen for this version of the 5830. It's a dead ringer for the non-reference cooler used on their HD 5770 video card. That might seem like a big downgrade, but even though the Juniper chip is half the size of the 58xx series Cypress chip, the little bugger runs at 850 MHz.
Thermal performance is more dependant on clock speed than number of transistors (remember the Pentium 4 space heaters...?), so don't dismiss the 5830 cooler as a lightweight performer. Of course, there are no free passes on Benchmark reviews; we'll examine the card's actual cooling performance in our testing section, a bit later.
The XFX Radeon HD 5830 is not exclusively based on the 5870 design, like the prototypes from ATI were. It's a brand new board that incorporates a new power supply design with the muscle of the 5870, but without the complexity and flexibility of software voltage control. The overall size of the card is similar to an HD 5850, and this was achieved by both simplifying the power supply section and using the latest technology for the VRMs. The four small, square chips next to the iron-core chokes are DrMOS (Driver-MOSFET) chips from Renesas, which integrate three discrete power devices into a single chip, while occupying only half the space. We'll provide more detail on the power supply design in the next section. For now, let's just say that the availability of smaller, more highly integrated power chips couldn't have been timelier. XFX recommends a minimum PC power supply rating of 500 watts for systems that use this card. That's obviously going to depend on what else you have in the box, but the peak power numbers (175W max) are also there for you to use, if you need to perform a more detailed analysis.
The build quality of the XFX card is excellent. The heatsink-fan assembly is a well thought out design that is executed perfectly. Attention to detail is clearly evident, as the tiny fan cable tie-down clip demonstrates. A part like this could have been easily left off, or been deleted by a budget-conscious product manager, but then half the users would have cursed the unruly cable routing as they installed the card in their systems. Somebody cared enough about the user to put it there, and leave it there when challenged; that small act speaks volumes to me.
The back of the board is pretty standard for a card in this class. There are fewer components mounted on the back side than you might see on an HD 5870 for example, if you took the full-coverage metal back plate off that card. Part of that has to do with the simpler power supply design; there is only one PWM controller mounted here, instead of the three separate ones on the more expensive cards. The GPU cooler is mounted with four screws and the help of a flexible, spring-loaded back plate. The dark, grey-green color of the PCB itself is a common feature of all the XFX Radeon HD 5xxx cards, and looks suitably industrial; in fact it looks just like a type of conformal coating that is used on cards designed to operate in harsh environments. It's not, because those specialty coatings cost a whole lot of money, especially the types that are meant for high speed circuits.
The assembly quality of the board itself is up to modern SMT manufacturing standards. The component placement and solder quality is quite good, as you can see here; this is the area on the back side of the board, directly below the GPU, and is one of the most crowded sections of the board. It is also one of the most critical sections for build quality, as any variations in stray capacitance here could impact the performance of the board, and certainly its overclocking ability.
ATI made the decision to reduce the number of Stream Processors a little more aggressively than they did when they created the HD 5850. They "took away" 320 Shaders this time, instead of only 160. This accomplishes two very important things; it keeps the HD 5830 far enough away from the HD 5850 to prevent cannibalizing sales of that very popular card. It also helps ATI "recover" more defective Cypress GPU chips, which is very helpful when your supplier is having extended manufacturing yield problems with their latest technology node. The downside to only having 1120 Stream Processors is that the GPU had to run a fairly high clock rate in order to hit the performance target that was the whole reason behind this product's very existence. ATI wanted the HD 5830 to hit the exact middle of the performance gap between the 5770 and 5850, too far one way or the other and you haven't really filled the gap. Based on their internal testing, ATI feels they hit the mark. Pay attention to the scaling of this chart....the key takeaway is how close to the middle, between the high and low bars on the left and right, that the HD 5830 bar lands.
So, the stock clock for the HD 5830 came to be set at 800 MHz, and we have the strange situation where the lower performing HD 5830 actually pulls more power than a stock HD 5850. We'll examine the impact of these design decisions in our testing section. For now, though, let's look at some of the features of the XFX HD 5830 in more detail.