Diablo showed very very few hardware errors (according to the forums, it was low .. less than 3 in 1000 for any card, and in some one case only 1 in ~2000)
Hardware errors? Any hardware error means you've pushed the boundaries of either: voltage, clock speed, or heat... Reduce one
No it doesn't. Go read carefully. Hardware checks are turned off intentionally by Diablo (and I believe all GPU mining software) and there are always going to be occasional hardware errors for this kind of thing (there is for just about all hardware which is why there is FEC, CRC, and other error control protocols for all devices depending upon what they do ... your CPU is a bit of a different beast, and I am not sure how error handling is done there, but I assume there must be occasional errors of some kind]. Excessive hardware errors on the other hand does imply it is pushed beyond limits. I can tell you that all of my cards passed the Furmark hammer
Not quite the same as mining obviously. I have not pushed any card very far when it comes to core clock speed and only the 5850s had memory speed reduced [900MHz to 700MHz] and they had the least errors anyway [all being low, but especially those]. The temperature on all of the cards is never allowed to exceed 80C as my limit, but in practice, none have ever been higher than 78C for any amount of time and normally my hottest card is 73C (two almost mirror each other ... different models, cases, rooms (office and cement basement floor) and one doesn't exceed 68C ... just better airflow and heat sink in or something). MSI Afterburner monitoring all of them. The highest errors [which as I said, were very low] are on my 6970 and that is the card running in my primary workstation that I am using right now and it has Aero running always, a lot of processes going on, moving windows around often [which uses 3D hardware acceleration when Aero is on] and lots of other services [with priority] running on this machine [including Windows Media Center pulling OTA HD broadcasts down, although I don't typically watch them as I usually get what I need via TiVo].
It is worth determining what a hardware error is for any given device. Ethernet cards, for instance, are loaded with them, but they correct for it and there is also correction in the Ethernet layer protocol itself to handle retransmits as needed [i.e. due to collisions]. In the case of a GPU using OpenCL, I do not know precisely what would cause a "hardware error" as determined by Diablo. I suspect bus communication errors [data moving in or out fails a checksum or parity check ... whatever] and could be due to voltage, speed, PCIx bus, etc. It could be true hardware faults from too much heat, too fast of processing without enough supporting power, or memory errors due to similar. Many reasons. Hardware as complicated as a video card [especially the GPU itself] will always produce errors, but it depends on what type of errors and how often whether it is a problem. For instance, if hardware error checking was turned on, it may self correct or recompute .. whatever [I am speculating, I need to look it up to be sure]. Also, with video for instance, certain types of errors result in essentially unnoticeable changes (maybe a pixel is shaded slightly off, or a vector skewed ever so slightly .. again, hypothesizing), and thus, are accepted by the manufacturer (AMD in this case). Different uses have different tolerances to different types of errors. Look at your cable model or DSL modem and if the information is there, you will see lots of error stats like correctable errors and uncorrectable errors. The latter, in that case, is information that it had no ability to correct and are usually external to itself. Correctable errors are errors that may be externally caused [usually are], but error correction protocols were able to fix the error without a resend [meaning, FEC, CRC, parity and other methods which can essentially determine the bit that is incorrect and fix it]. Error correction in the case of communications means overhead in both bandwidth usage and computational analysis of the stream [and thus some latency]. My point is only that errors cannot be eliminated, only compensated for or dismissed as acceptable and dealt with either by redoing the work or simply ignore the results [with video and audio, it is usually fixing it via some error correction mode and anything that escapes that is deemed acceptable, or rather allowed to pass with the assumption that within design limits, the errors are not significant ... so bad hardware is often still usable with lots of errors and you get to suffer the effects of say, marcro blocks or pixilation or with audio, clicks or silences, etc.].
All this writing and all I really said is that hardware errors are normal and does occur with ALL GPUs. Excessive hardware errors are not and the definition of excessive depends on the hardware and its intended function; I am not sure what is excessive with GPUs in general, but with hardware correction turned off by Diablo, the author indicates 3 in 1000 [shares] is just fine. I saw less than that on all GPUs.
