"A long time ago, this was my first desktop Mac (7600/132 originally) and this is the 6th (!) CPU upgrade for it. In order:
PowerLogix 604e/225 (~$290, plus ~$120 for a 1MB L2 cache dimm)
PowerLogix G3 350/175/512k ($159)
XLR8 Carrier G3 466/233/1MB ($189)
NewerTech G3 500/250/1MB ZIF for above carrier (got it free, NIB)
Sonnet Crescendo/PCI G4/400 (also free from a DOA 8500)
Sonnet Crescendo/PCI G4/1GHz ($159)
This machine currently gets use in my remote office on the other side of
campus about an hour a day and it certainly didn't need an upgrade from the
G4/400 but Sonnet had the 1GHz upgrade for 20% off for MacWorld 2007 which
brought the price to $159. So I decided to make a *hobby* purchase (and
oddly enough it was the cheapest GHz class upgrade available at the time).
First impression: Looks good out of the box, similar to the G4/400 but with
a low profile fan on the heatsink where the G4/400 just has the passive
heatsink. I don't like fans for long term use as they wear out, I had one
on my NewerTech G3/L2 300/200/1MB which did.
There is a CD installer for a G4 startup PRAM patch, Sonnet driver (OS 9),
Metronome (OS 9), and L3 Cache enabler (OS X). Booted to OS 9 and ran the
patch anyway even though I was already using a Sonnet G4 and switched the
cards. It didn't boot. Switched things back and it booted with the G4/400.
I'll condense the next number of experiments to:
Zapping PRAM means I need to start the first time with a 604e card in this
machine (I have a 604e/180 laying around) and then stepping up to G4/400
then G4/1GHz. After a few of those, I get the G4/1GHz working in OS 9.
MacBenched it (is this 1996?) and the numbers were big so it was working OK.
Metronome IDs the chip and all caches correctly. I don't remember what ASP
said exactly but it did say 1GHz but it may not have IDd the processor
correctly. Naturally OS 9 was extremely zippy but it was even with the
G3/350.
Now for OS X, which is the point of buying this fast processor. I had been
using this machine as a G4/400, OS 10.4.8 (thank you Ryan Rempel!!), 1GB
interleaved RAM, 18GB Barracuda on PCI ATTO UltraSCSI PCI, PCI Rage128, PCI
Apple 10/100bT (from Beige G3). Performance was good but of course, slower
UI/video than an AGP G4/400 (but still pretty good). I was hoping to get
some of that video performance back with the extra MHzs.
Restart in OS X and hangs on white screen. Run the whole rigmarole of
zapping PRAM (see above) and no love. I got it back in working order with
the G4/400 and tried again a few times over a 2 month period with no luck.
At one point it seemed that the ATTO card was preventing booting but I
eventually got it working again with the ATTO. I deinterleaved the RAM,
reduced it to 512MB, removed Rage128, removed 10/100, etc. & no OS X for the
1GHz G4.
Eventually I came back for more abuse and (with everything installed) zapped
PRAM, started in OS 9 with 604e/180, started in OS 9 with G4/400, started in
OS X with G4/400, started in OS X with G4/1GHz and the damn thing worked. I
may not have ever tried this exact, simple order before and in fact I
installed the G4/1GHz as a lark, not expecting anything, and it just worked.
The white screen came up for a second and then it booted OS X normally.
The OS X experience with this upgrade is hit and miss, mostly hit. The UI
runs very smoothly *except* with Safari, which I use a lot with this
machine. The scrolling speed drags to 1fps after a second or so. Also,
network transfers would stop after a few hundred megs and the 100bT
connection would be dead until restart! The PCI bus of these machines is
known to be imperfect, so I removed the 10/100 card and Safari scrolling is
much smoother but no faster than the G4/400. Network transfers are now
flawless (but slow!).
As far as the rest of the experience, it runs noticeably faster and
smoother. Dragging huge APOD-linked picture files to a HD folder is much
smoother, drag resizing large Finder windows with lots of data in them is
perfectly smooth, multitasking is much faster but still laggy with one
processor and a slow bus.
As far as pure CPU power, it performs like an ~800 MHz AGP G4 in video
conversion tests. I use iSquint to convert videos to h.264 and here are
some numbers from a 24 minute conversion of mine:
- DA G4/533 - 360 Min
- B&W G3/1.1GHz - 330 min
- PMac 7600 G4/1GHz - 250 min
- Saw G4/500DP - 220 min
- MacBook Core Duo 2.0 - 36 min
Video clip playback is maybe the biggest improvement as they were almost
always dropping lots of frames with the G4/400 and every one I've tried
(*except* h.264 encoded ones) are smooth with the 1GHz G4. H.264 is still
too much for this slow bus speed, video card, and PCI video bus. My G4/533
handles SD h.264 fine at home with a 4x AGP Radeon 9000.
Xbench 1.3 score was 25.5 total with IMO an anomalously high UI score (7600
G4/400 total was 14.5). A big L2 or L3 cache boosts the XB UI score greatly
(unrealistically?) as observed here, in the B&W G3/1.1GHz (1MB full speed L2
cache), and the new 7448 G4 upgrades (also 1MB full speed L2 cache).
I will test the removing the PCI Rage128 card to see if the video gets any
smoother with the onboard video but even if there are PCI bus issues, the
PCI Rage128 is still accelerated for OS X and the onboard video isn't, so
the performance may be a wash. I had an online discussion with someone a
few years ago who maintained that for Quartz rendering the 73-9600 PCI Macs'
onboard video was better because it's on a dedicated 50 MHz bus as opposed
to the sometimes-flaky 33 MHz PCI bus for a PCI Rage128 (Rage128 is still
faster/smoother for scrolling speed and window dragging in my tests). He
saw big differences in video display speed when using transparent terminal
windows which were a big part if his workflow.
Overall:
10 points for speed
-1 point for installation hassle (should be 2 points for most people, but I
like tinkering)
-1 point for PCI bus issues which I have not seen on 5 other CPU upgrades
-Tom"
