CompuServe Thread

#3DS &Pentium

8 messages in this thread
#141681From: David B. KnightDec 13, 1994 8:29 PM
J. Ruikis, What (if anything) am I to make of the "Pentium Problem" vis-a-vis 3DS? I have just sent off a check to a VAR for Release 4 and a P-60. I've been advised by said salesman that any advanced math that 3DS may call for the processor to perform out to 7 or 8 decimal places may (or may not) cause a glitch – possibly hidden, possibly not. At worst, it would be a rare and intermitant problem, and not necessarialy the Pentium's fault. I realize that this is early in everyone's awareness of the situation, but any and all information/advice would be much appreciated. BTW: Q. How many Pentium engineers to screw in a light bulb? A: 1.8322357454, but Intel says that 2 will do fine. :> Thanks, Dave Knight
#141805From: Jonas Ruikis [ADESK]Dec 14, 1994 12:30 PM
Here are some recent quotes from Gary regarding 3DS and then I've included a statement regarding ACAD….. ———————————- The Pentium floating point bug does NOT affect 3DS at all, and I don't even think it's likely that anyone would ever run into it with AutoCAD within their lifetimes. Don't worry about it and get a P90. – G The Pentium glitch should only show up in double-precision floating point operations. Since 3DS only does single-precision ops, it shouldn't affect you in the slightest. – G ——————————— Autodesk, Inc. 12/07/1994 AutoCAD and INTEL's Pentium Floating Point Flaw Intel has been shipping Pentium chips for almost two years. The majority of Autodesk CAD products use double-precision floating point math, including all AutoCAD releases such as Release 12, AutoCAD LT, AutoSketch Release 2.0, and all products that run on top of AutoCAD like AutoCAD Designer, AutoSurf, AutoVision, and AutoCAD Data Extension. To date Autodesk is not aware of any customer having a problem due to the reported floating point unit flaw in the Pentium chip. And based on the information provided to us so far by Intel, we believe it is unlikely that any Autodesk customer will be affected by it. Although we believe this situation to be receiving more attention than it deserves, we will continue to monitor it, and we will take action as necessary to help alleviate this problem for our customers. Cary Fulbright Strategic Marketing CAD Autodesk, Inc.
#142866From: David R. SwobodaDec 20, 1994 1:22 PM
>> The Pentium floating point bug does NOT affect 3DS at all, and I don't even think it's likely that anyone would ever run into it with AutoCAD within their lifetimes. Don't worry about it and get a P90. – G >> Gary, Just curious, but Stuart Ferguson (on LW prog team) has said on the INTERNET that Lightwave Windows/NT will most likely be affected by the PENTIUM error 'cause they do dblprec MATH. Just wondering the Plus/Minus of DblPrec MATH and why they (LW) use it and you guys don't? And if v5 is Windows will this make a difference for your guys at YOST? Thanks, David.
#142872From: Yost GroupDec 20, 1994 1:43 PM
We don't use double-precision math for two reasons: 1) it forces your models to take up TWICE the RAM, and 2) it's slower. – G
#142910From: SyndesisDec 20, 1994 6:09 PM
Hey, I asked that question on the Internet. 🙂 It's entirely possible that LW is using doubles for rotation an matrix calculations. Seeing that the models clearly only use single-precision for points, like 3DS, I doubt they're using doubles to re-calc points. And this is the 3D Studio forum – how do you expect the Yost Group to make assessments of the internals of another program?
#143825From: Anthony RamirezDec 27, 1994 2:57 PM
>Just curious, but Stuart Ferguson (on LW prog team) has said on the >INTERNET that Lightwave Windows/NT will most likely be affected by the >PENTIUM error 'cause they do dblprec MATH. In case you didn't see his correction, Stuart made a typo in his message, he meant to say it `wouldn't affect it'. If you read the rest of the message you will notice that that is what he meant. Btw, he was only making reference to the modeler and not the renderer. <<< Tony D. Tracer >>> (Any render time >0 needs acceleration.)
#145517From: David R. SwobodaJan 7, 1995 4:14 PM
Thanks Anthony, My Bluewave reader is notorious for hammering messages. I checked again between the lines and your right on……. David.
#142372From: Frank ZuccaroDec 17, 1994 2:53 PM
We offer network rendering services to clients using up to eight (8) Pentiums, 60,66, & 90's (and DX2's) – and have not encountered any problems attributable to 'math' errors. Over just the last year, this adds up to thousands and thousands of renderings. Some jobs are 5,000 to 9,000 frames each (compounded by the fact we field render everything). In the old days, back when we used the Weitek NDP chip, we'd load alternate 3DS.EXE and I.P.A.S. routines (optimized for the Weitek's superior performance). We'd sometimes (not always) choke when pushed the Weitek past its rated clock speed (putting a 33Mhz Weitek into a 50Mhz DX, etc.) We discovered that we could intermittently 'hang' the renderer if Phong shading was invoked. The fix was obviously not to push process the Weitek. But even this wasn't a legit' 3D Studio/NDP problem.