Retail Radeon R9 290X Graphics Cards Slower Than AMD's Press Samples 111
crookedvulture writes "AMD's recently introduced Radeon R9 290X is one of the fastest graphics cards around. However, the cards sent to reviewers differ somewhat from the retail units available for purchase. The press samples run at higher clock speeds and deliver better performance as a result. There's some variance in clock speeds between different press and retail cards, too. Part of the problem appears to be AMD's PowerTune mechanism, which dynamically adjusts GPU frequencies in response to temperature and power limits. AMD doesn't guarantee a base clock speed, saying only that the 290X runs at 'up to 1GHz.' Real-world clock speeds are a fair bit lower than that, and the retail cards suffer more than the press samples. Cooling seems to be a contributing factor. AMD issued a driver update that raises fan speeds, and that helps the performance of some retail cards. Retail units remain slower than the cards seeded to the press, though. Flashing retail cards with the press firmware raises clock speeds slightly, but it doesn't entirely close the gap, either. AMD hasn't explained why the retail cards are slower than expected, and it's possible the company cherry-picked the samples sent to the press. At the very least, it's clear that the 290X exhibits more card-to-card variance than we're used to seeing in a PC graphics product."
the cards run at higher temps by default (Score:5, Informative)
This has been discussed in many places like toms hardware. Essentially they found the cards volting is determined in the bios and the fan speeds can be altered. change the bios which many have released and the undervolting which occurs at lower temps is solved. Sapphire already released a new bios for the card to make these changes to keep them consistent yet keeping them from going above 95 degrees.
Throttling + OEM fan speed and grease variance (Score:4, Informative)
Toms Hardware covered this pretty extensively [tomshardware.com] a month ago.
The short story is that AMD is throttling clock speeds to hold within a temperature limit. They learned the hard way that 40% PWM does not equal 40% fan speed, especially across all fans the OEMS used. There's a driver fix for that now measures fan speed and adjusts accordingly when in quiet mode that eliminates most of this performance discrepancy (retail cards can now see higher performance in line with review samples).
Remaining differences between cards may be due to different heatsink grease, also already examined by replacing the grease on a retail card [tomshardware.com] for a significant performance gain.
Re:the cards run at higher temps by default (Score:5, Informative)
At this point it's reasonable to assume that AMD cherry-picked the cards they sent reviewers to make sure they were as good as they could be.
Re:I never got the fascination with AMD/ATI (Score:3, Informative)
Not that FIX / Thermal performance (Score:5, Informative)
If you bothered to RTFA (I know!), you'd see that they indeed checked this out. They flashed the BIOS of their sample card onto their worst performing retail card. There was a small difference, but far from enough to make up for the gap between that card and the sample unit they received from AMD
Not that BIOS. As other have pointed in the thread, the variation in performance is more or less linked to the variance of thermal management.
Not all PWM Fan behave the same. There's a *newer* BIOS version (not as in "use the one that came with the sample" but as in "download the latest version that was made available on the manufacturer website, betwen when you bought it and now").
This version of BIOS is better at computing what signal it should send to the fan to have better cooling.
And once the cooling is improvent, the card will automatically scale up its speed.
Also, there can be difference in thermal grease, etc.
At this point it's reasonable to assume that AMD cherry-picked the cards they sent reviewers to make sure they were as good as they could be.
Or, instead of cherry-picking, maybe there's some build quality between the first engineering sample sent by AMD, and the mass-produced card by NONAME asian manufacturer ? (Or even mass-produced cards by very popular brands that have to fulfill lots of orders ?)
Difference in quality of the fans (NONAME will pick whatever is currently the cheapest, and even with popular big-names, there's going to be some variance, depending on where the current batch was sourced).
Difference in quality of thermal conduction of the interface. Difference of quality of thermal grease (NONAME will pick the cheapest, bigname might have variation in batches, specially if they source batch from several manufacturer to keep up with the pace). Difference in quality of work (NONAME might even do a sloppy job in applying the thermal medium to the radiator).
You end up with exactly the same chip produced by AMD, but vastly different thermal condition, all this with a firmware and a driver which isn't yet best at fan throttling, and you end-up with some measurable difference in output. ...BUT...
Pick up Nvidia cards, and you're going to see exactly the same effect.
Either card that vary in their performance (or that have big variation in temperature, depending on how the current firmware throttles the card)