Derek Smart on ATI Driver issues

I'm glad this topic was brought up. Developers should NOT be working around driver issues for different IHVs. Now that I've got that off my chest... do you know how hard it is to debug an application that behaves differently for different video cards? Or, what if IHV X has incorrectly implemented feature Y, so application Z takes note of this and uses this incorrect implementation. Now IHV W is SOL because the application is using the wrong implementation for a feature.

This is why IHVs have devrel people: Report bugs to them so they can be fixed!

It's bad enough that drivers need to be hacked for applications that do silly things (like crash if you report too many texture formats... this is a famous one), but having to put bugs into the driver so the behavior matches another IHV's driver is ridiculous.

 

Jeff Royle from ATI Dev Relations posted that on Rage3D a year or so ago..

 

The way I see it, as Derek Smart so abrasively put it, sometimes it's necessary to get your game to work on video card X. Of course, at the very least, the program should most certainly check that it's a video card from the manufacturer who has the bug...that is, these workarounds should only affect the hardware that has the bug.

Well, at least from Derek Smart's perspective, he has been reporting bugs, then working around them when no response was emminent.

 

This is the general gist of feeling I get with all my dealings with ATI regarding my work on Rage3D Tweak. They won't put OCing in the drivers for the reasons you listed and others, but they are happy that we provide that capability to their users... they'll even answer some questions now and then if we bug them enough.

 

honestly though...

If they conceal the overclocking altogether...but pop it up when some obscure registry key is detected, such as "MrMcGoo," then I don't see the problem.

Heck...I know it's somewhat unfashionable to do a 1-to-1 comparison between nVidia and ATI...However, nVidia even now provides an overclocking panel with their reference drivers...

This may seem like a small thing...But, when you read between the lines, I think it's somewhat obvious (at least to me) that the reason it's in there is to dispell the notion that nVidia's standard reference drivers are/were inferior to ATI's, and that ATI provided a heck of a lot more control for their products...

In essence, it's my opinion that nVidia users can directly thank ATI for providing the incentive to have such a control...

Likewise, I wouldn't be all too surprised to see ATI do the same.

Is it a coincidence that this last nVidia driver finally provided a control for D3D Anisotropic Filtering? I mean, how long has that feature been available now? Does anybody honestly think they hadn't read some of the comparisons where reviewers stated, "We refuse to use a 3rd party hacker or registry hack to enable this feature...therefore, we're going to show you how good/bad nVidia's products look compared to the Radeon's when their A.F. selection is enabled."

 

good point type, but i think, in likelihood ATi wont provide a overclocking "tab." Why?

well clearly, there are samples of the r9700 out that overclock really well, but its a high possibility that there a good deal of boards that do not. we know for a fact the chip is running pretty hot, and 325MHz is a generous clock speed... if a user were to read that anand got his r9700 to 400MHz then try that on his own and completely melt his whole board/agp slot.... it could be really bad for ATi LOL.[/u]

 

It's only availible with coolbits.

 

Ouch... i wonder who that could be talking about?? *cough*nvidia*cough*... Like that irritating issue when tribes 2 first came out.. Where the only cards that correctly supported the way fog covered buldings in the distance (way laymen I know, I know) were Nvidias. Everyone elses cards had *bugs* that made the buldings blink and act all quirky as they got covered by distance fogging. It turns out it was becuase of some quirky way that only Nvidias openGL code handled the situation.. and they coded *specifically* for that only.....

i see what you mean.

 

A big problem is lack of testing on the part of the ISVs. It used to be that everyone tested their stuff on 3dfx and that was that. That is how many of the "if texture format X isn't in the right slot, we'll get corruption" and "if too many texture formats are reported, we'll crash" bugs popped up. Now things are more subtle. Like, "let's use the last 32-bit format, whatever it is" bugs. DX8 changes this because you have to request a format and DX8 tells you if it is available, so at least we can avoid these simple problems

Now, 3dfx is gone, but many ISVs are limiting their testing to another IHV's products, so we get more of the same. If a driver bug is encountered, ISVs assume the fault is their's or just work around it to make things work. History has this way of repeating itself.

 

Alternatively they want to hold something back for when they do the DDR-II versions of the board...

 

I remember that one as well

K-

 

hmm in his rant DS is very definite that the ATI drivers regularly break basic behaviour like fog. Or is it a case he appears to think ATI drives break it, because he is used to coding in a certain way?

DS is a D3D programmer right and JC seems happy right now with ATI, but that would be OGL and all the bugs listed for the 9700 seem to be D3D games (maybe because there are more I suppose). What can be read into that?

 

The "power" and "enthusiast" crowd can already download Rage3D Tweak or Powerstrip, the first of which is free. We don't need ATi to add an overclocking tab to their drivers, and it's probably better if they don't (although you have to be pretty stupid to be able to kill your card via OC'ing...I mean you really have to push the limit and ignore the fact the card keeps locking and/or severe graphical glitches).

So, anyway, if I were them I just wouldn't bother. Leave it to the enthusiasts to take care of themselves.

 

I disagree completely...if some cards can overclock to 400 MHz (and it seems to be more than one) then it's not true at all that 325 MHz is a generous speed. In fact I guarantee 325 MHz is conservative so that ATi can maximize yields while still getting stellar performance.

A 400 MHz R9700 would kill a Ti4600 all the more, but at what cost in yields? There's just no real point for them to push the envelope and sacrifice chips when Nvidia has no real competition for them (how times change, LOL).

 

can't speak of the r200 / r300 drivers, but the r100 (presumably) drivers used to have problems with fog on a regular basis. i have recollections of having to come up with a special r100 path where vertex fog was used instead of exponential, which was used in the common path, as per-pixel fog behaved differently with each new r100 driver release (but overall incorrectly). eventually the title ended up looking a bit different on the r100 in the fog aspect, i.e. on r100 it was linear and on the rest of the cards - exponential. admittedly, on some of the other cards vertex fog was broken, which, aside from the artistic reasons, was the main (technical) reason to prefer exponential fog in the common path.

at that time, i, too, asked myself how could such basic features be so broken (and not only with r100's pixel fog but with other vendor's vertex too)

 

Aside from yields and competition, I imagine there are heat and power issues.

325Mhz to 400Mhz would represent around a 23% increase in clock speed. Wouldn't that also mean a 23% increase in heat output (correct me if i'm wrong on that one)?

If that is the case R300's current heat output of 50 watts would jump to about 61.5 watts, and if you increase the clock speed you really should increase the memory speed too which would further increase power demands right?

Regardless of all that stuff I'm sure ATi will figure out a way to make things faster.

 

bugs in the silicon perhaps. I take it its acceptable to suggest there are going to be minor bugs in the silicon of products

 

sure. but i'm also positive that even if the title publisher had put up with that, the title's customer wouldn't have been pleased if i had just waved and said 'aah, what the heck - fog's out of order, the customer expects for such things in the sillicon & drivers anyways.'

 

oops...

What happened is that I uninstalled the newer Det. drivers, but didn't do a full reboot to clear out the registry...So, when I reinstalled the drivers, it preserved the registry settings.

In doing so, it gave me the impression that the overclocking panel was there by default...But you're right, you still have to provide the CoolBits registry key/value in order to see it.

 

oh no I meant acceptable on this forum, you know how touchy people can get

of course the customer wouldn't find it 'acceptable'