Conclusion on Linux Benchmarks

I didn't entirely expect the Radeon HD4850 to play completely on par with the Radeon HD3870 in Linux. It's kind of disappointing to see the performance I saw in Windows diminish so much in Linux. This makes me wonder if there's an issue with AMD's Linux driver that goes beyond just performance compared to Windows. For two different GPUs to score almost equally in most of our benchmarks makes it seem like there's some kind of enforced cap on the Linux driver in terms of performance.

Those at AMD we've been priveleged to speak with have only told us that the Linux driver simply hasn't been properly optimized, but a future release should correct this issue.

Regardless of these issues, the Radeon HD4850 did fall where I expected it to. Despite the performance gap in Windows against the nVidia family of cards, I did expect the Radeon HD4850 to fall behind these cards in Linux. As I've said many times before: nVidia's Linux driver, while not perfect, is still superior to AMD's.

Temperature & Noise

Since the X-Qpack is a small-form factor case, space is tight and wires are fairly abundant. The power supply is directly above videocard, and there's a single 120mm fan on the rear of the case, in the corner opposite the videocard. Suffice to say, there isn't a lot of cooling options. Although the 9600 GSO maintained respectable temperatures, I think a lot of it had to do with the dual-slot cooler.

The Radeon HD4850 runs idle at a whopping 65°C, and heats up to a burning 77°C under full load.

That is, it runs that hot until the firmware has been updated to the latest version. Production-ready samples should already have the latest firmware, but if not, get it. The new firmware significantly lowers temperatures to 42°C; at idle, and 56°C under a heavy load. That's far better than what I saw before.

The fan on the HD4850 isn't overfly loud. With the PC only about 2.5 feet away, the fan is barely audible. I'm sure if it was being used in a media center and connected to a TV, it wouldn't cause much of an issue with noise. Performance and low noise output are definitely advantages of this card.