#3D Stuio + Pentium???
3 messages in this thread
The important thing to keep in mind about 3DS and the Pentium is that the
general-computing magazines are talking mainly about INTEGER speeds, since
that's what's important for general-purpose computing. 3DS renders, however,
are largely FLOATING-POINT bound. The Pentium is only about twice as fast as a
486DX at the same clock speed for integer operations (three to four times for
programs specifically compiled for the Pentium), but is from five to ten times
faster than the 486DX at pure floating-point ops. The reason is that the
on-board FPU ("80587"?) is MUCH more efficient than the equivilant "80487" FPU
built-into the 486DX.
No program can be 100% FPU (integer-based operations are needed for the
communication between the CPU and FPU), but 3DS2 rendering comes pretty darn
close. The benchmarks posted in various threads here show that 3DS2 renders
roughly four times faster on a Pentium/60 than on a 486 DX2/66.
Bottom line: don't believe the magazines when they say the Pentium won't be
as much help as Intel would like you to believe. That's true when you're
talking about word processors and databases and the like (which is what most of
their readers use computers for), but NOT when talking about 3-D rendering and
other FPU-bound tasks! THOSE types of applications are sped up CONSIDERABLY,
by at least a FACTOR of three!
That said, the PowerPC looks even more promising, being faster, cooler, and
cheaper than the Pentium. Unfortunately, it only runs DOS programs via
emulation, which would negate much of the performance advantage. But if 3DSr3
comes out in a Windows NT version, it should run QUITE fast on the PowerPC.
The currently-available PowerPC 601 chip at 66MHz (same as the best current
Pentium chip) runs over 80 SPECfp92, vs. 56.9 SPECfp92 for the Pentium. It's
worst case power usage is only 8.5 watts, vs. 16 for the Pentium, which
translates into less heat generated. The die size is 120 square mm, vs. 262
for the Pentium, which means a physically smaller chip (10.9 mm on a side vs.
16.2 mm) which in turn means smaller motherboards.
Forthcoming PowerPC models include the low-power 603 for laptops and other
low-power applications, the higher-performance 605, and the VERY
high-performance 620. It runs Macintosh, DOS (via emulation), OS/2-Win,
Windows NT, UNIX, and many other operating systems. The 601 is the first
tangible result of the Apple/IBM/Motorolla alliance.
Yost, PLEASE consider making a 3DSr3 for Windows NT, with a version
specially compiled for the PowerPC!
Marion,
I agree with your assertions about floating point vs. integer performance on a
Pentium relative to a 486. I looked around here for some 3DS benchmarks (I
don't run 3DS but I was curious to see how an existing program that I assumed
used a lot of floating point ran) but didn't see any. Maybe they scrolled off
before I started looking…
MM> The currently-available PowerPC 601 chip at 66MHz … runs over
MM> 80 SPECfp92, vs. 56.9 SPECfp92 for the Pentium.
Are you saying the PowerPC 601 is running 80 SPECfp92 when emulating a
80×86+80×87? That WOULD be impressive.
What I'm saying is:
1) Now, 3DS won't even run under a DOS box from Windows or OS2 and probably
won't work under DOS emulation under NT on any other platform. Even if it does
run, I expect it will run much slower than on a Pentium unless the host
processor has an FPU that is instruction set compatible with the Pentium. If
I'm right about this, there's no point in getting a PowerPC now to run 3DS now.
2) I would guess that 5 to 10 percent of 3DS is coded in assembler for speed
and that the rest of the code was not written with portability in mind. I
wouldn't expect to see a Pentium NT port in less than a year. An NT port to
another processor probably won't be around for a year and a half or so.
I agree that once a native PowerPC NT version of 3DS is available, that it
will, in all likelyhood, run much faster than the Pentium version. Of course,
by then we'll be running Hexiums or Septiums or something, but I expect the
RISC machines will be able to keep their performance edge since the Pentium
decendents will have to maintain 8086 compatibility.
I don't know if anyone really cares about power comsumption or footprint in a
rendering engine. All my PC's (2) are in tower cases with 300 watt power
supplies. You're talking a few cents a day more to run a Pentium than a
PowerPC, and maybe a few dollars in fiberglass for the motherboard. Portables
are another thing entirely… And Pentium systems will cost a little more
since the chip itself is more expensive. I suspect that most people will
accept the extra cost for full DOS compatibility though.
John.
John,
While comparing Pentium's to PowerPC's, it's interesting to note that
Intel has plans to release the 686 in one year and a 786 in two. My guess is
that the Pentium is last x86 compatible chip from Intel. Beyond that, x86 will
be software emulation only. Freed from 80's era shakle, I'd wager that Intel
expertise, _deep_ pockets, and experience will produce chips that will burn
past Alpha's and MIPS in low-cost and speed. Intel has no hesitancy towards
predatory practices.