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- Newsgroups: comp.sys.mac.misc
- Path: sparky!uunet!zaphod.mps.ohio-state.edu!caen!nic.umass.edu!risky.ecs.umass.edu!kirk.ecs.umass.edu!breck
- From: breck@ganzer.ecs.umass.edu ()
- Subject: Re: Information on: The IIvi, IIvx, and Performa 600
- Message-ID: <1992Aug16.210017.1816@risky.ecs.umass.edu>
- Originator: breck@kirk.ecs.umass.edu
- Sender: usenet@risky.ecs.umass.edu (USENET News System)
- Nntp-Posting-Host: kirk.ecs.umass.edu
- Organization: University of Massachusetts, Amherst
- Date: Sun, 16 Aug 1992 21:00:17 GMT
- Lines: 60
-
- Someone emailed to me (Liam Breck):
- > in comp.sys.mac.misc you write:
- > > The IIsi's only advantages are slightly better CPU speed (not a big
- > > enough difference to notice in real time use, but you will notice the
- > > disappointing screen redraw speed) and the ability to plug in Nubus
- > > cards, again, not an issue because the LCII is a very popular machine,
- > > so there are a lot of cards for its PDS (processor direct slot).
- >
- > You want to justify this? The si uses a 32 bit bus, not a 16 bit bus, so is
- > about twice as fast. Same reason an SE/30 is twice as fast as an LCII. Also
- > an LCII has max memory of 10MB. That doesn't leave much room for expansion.
- > I have 8MB on my SE/30 right now and plan to go to 20MB in a month or so.
- > I'd be pissed off if my machine maxed out at 10MB.
-
- This is a common misconception. Actually, the IIsi is about 28%
- faster, which is not enough to notice in most real-time applications.
- When doing something very CPU-bound, you might notice. That is to
- say, if you usually complete a coffee break while compressing a large
- archive with an LCII, you will have a bite of doughnut and sip of
- coffee to go when the same task finishes on a IIsi. :-) This 28%
- difference in speed is mostly accounted for by the difference in
- processor speed beetween the two machines -- 16MHz vs. 25MHz. The
- *IIci* is something like twice as fast as the LCII since it's clock
- speed is 33MHz. The bandwidth of the memory bus is really not
- critical in personal computers, 'cause other bottlenecks hold things
- up before the bus width does. For instance, the 80386 is only 4%
- faster than the 80386sx, which has a 16-bit external memory path.
- It's the same in the case of the Macs; you'll find that the original
- Mac II is only 4% faster than the original LC (both 020s at 16MHz).
-
- A really critical issue, though, is screen redraw time, since most
- real-time apps (word processors, drawing apps, the finder, etc.)
- redraw the screen a lot. The LCII uses the latest Apple on-board
- video standard, which includes dedicated, dual-ported VRAM. The same
- stuff that the Quadras use, only pared down for the LCII. It's very
- fast compared to using the main memory for video (the IIsi and IIci do
- this). You can speed up video on the latter machines by making your
- RAM cache huge, but that's another subject, see one of the columns in
- the current MacWorld (sorry, forget which one) for more info.
-
- Another point about video... Since the LCII can use a low cost VGA
- monitor (I got a Trinitron screen for $350) it really lets you save on
- the monitor. To get the same quality on a IIsi, expect to shell out
- the bucks!
-
- The 10MB limit on the LCII's memory expansion is unfortunate, but not
- unacceptable. I have 8MB in mine, and run a whole heap of concurrent
- applications and I haven't run out of memory yet! If I was going to
- use Quark and Photoshop at the same time to work on some layout, I
- would buy a IIci (or one of the future Macs) and a lot of memory, not
- a IIsi and same.
-
- So, when the whole story's told, the LCII is a better machine
- price/performance wise than the IIsi. The only reason I can think of
- to buy a IIsi is if you absolutely have to use a Nubus card. But
- since the LC(II) is the best selling Mac ever made, I don't expect
- you'll find a lack of cards for it...
- --
- Liam Breck breck@zonker.ecs.umass.edu
-
-