Intel vs. PowerPC and clock speeds. or intel vs. mac speed differences.

In My Humble Opinion
1

Okay, I don’t want to start a flame war here, but people tell me all of the time that PowerPC clock speeds aren’t comparable to intel, nor intel to AMD for other reasons. Now, I just bought a 1.42 Mac mini, and there are several times that I use my computer that just scream “weak processor.” I am pretty well confident in my computer abilities. And I bought an Athlon XP 2700 around two years ago. Well, I didn’t buy it, I bought the Mobo, processor, and the memory. So that was pretty much a new comp, but anyways.

Maybe it would be better for me to detail my experiences in the “types” of performance that each machine excels at.

Playing Divx and DVDs, Sometimes when I use VLC or Mplayer, and I simply roll my mouse over the dock (I have the magnify option enabled), I get skipping in the video. This is quite bad. On the other hand, the Mac is quite comfortable with PDF files using viewer, and is really great with windows. There is never any visible redraw of icons, etc. Why is that? Its really a nice stable feeling though. Never any kind of window movement stalling like on Windows. Another nice thing is the amazing stability of moving through a video. I can move through a video in Mplayer by pressing the forward arrow key which skips x interval. But on windows, I always crap up any player that even supports this kind of shuttle feature. Now my windows box had 1 gig of ram and this mac has 512 MB.

So its weird, I haven’t really played many games on my Mac yet. Partly because I’m not into games (except for Matrix Online) and then it only has a crappy video card, so what’s the point? So for games I have no comparison.

In general, however, apps seem to load slower on the Mac, but there seems to be no difference when I have a lot of apps open. On my Mac, I usually keep apps open by nature of the fact that its harder to close on windows, and the fact that it isn’t necessary to close them like on XP. Also on XP, your window management tool (The taskbar) is also where you keep programs that should be in the system tray. I don’t really like this though. I like the OSX way of having the Dock. Its pretty cool, and you can have your own “start menu” by having your apps folder in the dock.
But all of that aside, I have noticed several speed differences between my Mac and my PC, but its not a clear-cut argument. Video seems to be wierd and choppy at times. But other stuff is very impressive. Is there any clear way to correlate PowerPC and Intel CPUs?

2

Not really.

In non-geek terms (or as non-geeky as we can get and still be relevant), the difference between PowerPC and Intel-compatable processors is in their instruction set. PowerPCs are RISC (Reduced Instruction Set Chip), and Intel-etc.s are CISC (Complex Instruction Set Chip). To grossly oversimplify the tech involved, that means a PowerPC processor has a small number of operations it can do, and therefore can do every one of them very efficiently. Conversely, an Intel-etc. processor has a gazillion (give or take a bazillion) operations it can do, but isn’t as efficient at doing them.

Intel-etc. processors compensate for this inefficiency by running faster, which is why they have the higher Gigahertz ratings – and also why they’re a lot hotter than PowerPC-equipped computers. If you were to try to cram an Intel-etc. computer in a case like Apple’s Mac Mini, you’d have a melted puddle of plastic inside of an hour.

But to get back to your original question, there is no easy-to-follow formula for converting PowerPC clock speeds to Intel-etc. clock speeds; some people use PowerPC x 2 = Intel, but that’s a very rough rule of thumb at best.

As for the laggish performance of the Mac Mini, how much RAM do you have in there? That, more than anything else, will affect the Mac’s performance. Some folks are happyusing their Minis with just the stock 256MB of RAM, but I’d recommend 512MB (or even a gig) for a satisfying experience.

3

As rjung said, the more RAM, the better. Mac OSX, being a Unix-like system, works best with a buch of RAM. My little iBook G4 (1ghz) has 512 MB and runs rings around my fiend’s PowerBook G4 (1ghz) with 256 MB.
Another thing that is slowing your Mini down is the hard drive. It uses a slow Laptop drive, 4200 RPM IIRC. Most desktop drives are 7200-10000 RPM. Every time you hit the drive (which will be a lot if you only have 256 MB of RAM) you’re going to be slowed down by the drive.
To be completely fair if you’re going to compare a Mac to your PC desktop then you should use a desktop Mac. Apples to Apples.
All that being said I’ve noticed that in general my iBook is a lot faster then my 2ghz PC on somethings and slower on others.

4

Clock rates don’t mean much. You need to look at benchmark results, such as Specint (integer) and Specfp (floating point). Here is a 2 year old article with some - oddly I couldn’t find anything very recent.

I suspect there is probably some sort of gaming benchmark around somewhere. Do a search on specint and the processors you want. I would guess that most consumers don’t care anymore.

5

actually, I stated that “this mac has 512 MB” :smiley:

But no, I am VERY happy with the Mac. I am just talking about why certain tasks are slower/faster on my PC and my Mac. Obviously games are excluded because the hardware isn’t comparable, but the processor, according to rjung should be equivalent to a 2800 intel CPU.

I’m aware of the hard disk problem, but I would think that these problems I’m having playing videos wouldn’t be a hard disk problem. For instance, running the mouse along the dock? That should be done totally in the graphics hardware if I’m not correct. But it seems to be too fast of a skip to be a hardware problem. Even in Quicktime.

By the way, why does Apple offer iLife 5 with the mini, yet still won’t cough up on the full version of quicktime? I mean really? Not that I’m complaining, but I just think its strange. Its not enough that windows users have to use a shitty version of this software to play about a quarter of things on the web, but its really strange.

But I’m a Mac fan, and I’ll never go back. Its great and I love it, but there are a few minor annoyances that bother me.

6

Quick hint on speeding things up on the Mac:

1 - Go into System Preferences, and select the Dock icon.

2 - Where it says “Minimize using:”, select “Scale Effect” instead of the default “Genie Effect”.

I don’t know why, but this seems to make everything snappier, not just minimizing windows.

7

To make things more complicated, I would like to point out that modern Intel/AMD chips are actually RISC at their heart; they just use some fancy microops to maintain backwards compatibility. There is no inherent reason for the x86 design to be less efficient clock-for-clock than the PowerPC design, and note that several x86 processors have roughly similar performance to PowerPC designs at the same clockspeed.

The Pentium 4 chips are particually bad when it comes to heat, and have rather poor performance per clockspeed.

But the Athlon 64 chips are much faster clock for clock than Pentium 4s; and run much cooler as well; I wager you could get one of the mobile version working in a case the size of the Mac Mini. The Pentium-M chips Intel has also has pretty high performance per clock, and runs even cooler per mhz; given how small some of the thin & light notebooks are, getting a Pentium-M to work in a Mac Mini sized case pretty easily.

And generally, a Pentium-M or Athlon 64 has about the same performance as a PowerPC at the same clockspeed.

8

I worked for Intel for about 10 years. I helped develop manufacturing processes, so don’t have any in depth knowledge of microprocessor design.

My understanding is that the battle between RISC and CISC ended around the time the first Pentium processor was introduced. I believe processors have evolved towards a happy medium somewhere between the two extremes.

What’s important now is the number of instructions a processor can handle at the same time, how many processing threads can be handled at the same time, and how much level 1 and level 2 cache memory a processor has. Equally important is having software that can take advantage of these features.

Also, Intel and AMD have both announced their intention to introduce dual core processors sometime this year. This means having the equivalent of 2 CPU’s on a single chip. Again, to get the most out of these chips will required having software written to take advantage of the new design.

Clock speed doesn’t really tell you much about a microprocessor anymore, as indicated by Intel’s decision last year to start referring to their products by model number rather than clock speed.

9

Another thing about your mini is that it’s using an ATI 9200 graphics chip with a skimpy 32MB of video memory. I don’t know enough to definitively say if that’s affecting your video playback, but it wouldn’t surprise me.

Some of the other things you notice stem from the specific architecture of the Mac OS. The window server stores the bitmaps in memory for every window drawn by any app, meaning that windows never need to be redrawn on the fly and icons always appear intact. (The downside of that is that it can slow down performance, a real problem for the slower Macs Apple was shipping when OS X came out.)

You’re right about Quicktime Pro. Given that Apple sells $1,000 high-end video editing software, to chisel people for $20 for QT Pro’s basic, basic editing and playback functions seems very petty. Of course, they probably figure if you’re on a Mac, you’ll do your basic editing in iMovie.

10

Hell, I don’t care about editing, just fullscreen playback. I think it is pretty petty. I mean please. You give me OSX, iLife and all of this other stuff but not quicktime pro? how lame…

I just want fullscreen playback with video and audio contols (contrast, etc.) I haven’t found any player for OSX that allows you to adjust contrast and other things like that.