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Ryan1524 · Sep 21, 2003, 02:47 AM

i went to Carbon Comp today...think of it as the closest thing canadians get to an apple store. anyway, there was a 1.6 G5 which is connected to two displays. and that thing is slow. i mean SLOW. the dock is annoyingly jumpy and eveything was laggy. i don't expect this at all from a G5, but i guess since Jaguar is not 64 bit optimized and it's driving a second 18" display (wacom touch screen and 20" ACD), it has reason to be slow. then i tried the 1.8 G5, it's only driving a 23" ACD, and it's blazing fast, about 3 times faster than the 1.6.

another story, i tried a 1 GHz PB 17" in compusmart, it copied a disc in 5 minutes, compare it to a 1.33GHz PB 17" in the Carbon Comp store, it copied the same disc in 12 minutes, althou i didn't experience any slow down on the user interface. again, the 1.33 was driving a second screen.

i assume that a second display tax machines quite high by what i experienced. However, i never read of any complains from people about this. and afaik, a LOT of people puts a dual display on their macs.

so..is this true? was it an isolated case (2 cases actually)...? or is it perfectly fine and what i experienced was a coincidence??

please comment. thx.

Ryan1524 · Sep 21, 2003, 02:15 PM

nobody with a dual screen setup can comment??

geekwagon · Sep 21, 2003, 04:15 PM

I have dual screens on my Powermac (23" and a 1280x1024 LCD) and I never notice any slowdowns. I also run dual head on my 17" powerbook (another 1280x1024 LCD plus the internal) and I never experience slowdowns there either, except when the background changes. Even that has gotten better, because somewhere around 10.2.5 or .6 they changed it so that both screens don't change at the same time (it does one screen, then the other.)

I have noticed that a lot of the G5s I have seen setup in stores have their background set to change every 5 seconds. They feel really sluggish until you turn that off for some reason. Odd, since they did the same thing with the MDDs when Jaguar came out, and I don't remember them feeling particularly slow.

dopik · Sep 21, 2003, 04:36 PM

I had a G4 400Mhz with 2 screens. Both were at 1024*768 and I have never noticed any speed difference between the set up of 1 or 2 monitors.

dopik

hadocon · Sep 21, 2003, 10:48 PM

I have dual display on my DP800 - running 'top' shows no extra effort on the part of the CPUs when running with more than 1 monitor.

Gul Banana · Sep 21, 2003, 10:54 PM

I've never seen a slowdown when using dual LCDs.

superblue · Sep 22, 2003, 01:04 AM

I'm using an 1024 x 768 LCD and 1280 x 1024 CRT on a 733 G4 and have often wondered about slowdown... can't really put my finger on it but my G4 400 on a single CRT feels smoother and (sorry to say it) snappier...

I think part of it comes down to things like minimizing windows to the dock - which have physically further to go than on one monitor, and don't go so smoothly. But Finder resizing doesn't seem as smooth either... Could be imagining it, or it could be down to other reasons. Whatever - I wasn't surprised to read the title of this thread, that's all.

Riemann Zeta · Sep 22, 2003, 02:08 AM

Running a 1024*768 display and a 1280*854 display (both 32-bit color) without any problems. With a QuartGL graphics card and 64+ MB of VRAM, I do not see how multiple displays could be a problem, unless they were both 2048*1536, but even then, there should not be a huge slowdown.

Xerxes · Sep 22, 2003, 04:11 AM

I'm running a 22LCD with a 17inch side by side and no problems here.
Using a G4 QuickSilver.

There is the odd glitch when moving window to the second window if I have alot else going on, but other than that all is perfect...

Originally posted by Ryan1524:
i went to Carbon Comp today...think of it as the closest thing canadians get to an apple store. anyway, there was a 1.6 G5 which is connected to two displays. and that thing is slow. i mean SLOW. the dock is annoyingly jumpy and eveything was laggy. i don't expect this at all from a G5, but i guess since Jaguar is not 64 bit optimized and it's driving a second 18" display (wacom touch screen and 20" ACD), it has reason to be slow. then i tried the 1.8 G5, it's only driving a 23" ACD, and it's blazing fast, about 3 times faster than the 1.6.

another story, i tried a 1 GHz PB 17" in compusmart, it copied a disc in 5 minutes, compare it to a 1.33GHz PB 17" in the Carbon Comp store, it copied the same disc in 12 minutes, althou i didn't experience any slow down on the user interface. again, the 1.33 was driving a second screen.

i assume that a second display tax machines quite high by what i experienced. However, i never read of any complains from people about this. and afaik, a LOT of people puts a dual display on their macs.

so..is this true? was it an isolated case (2 cases actually)...? or is it perfectly fine and what i experienced was a coincidence??

please comment. thx.

Visnaut · Sep 22, 2003, 10:59 AM

I haven't been to Carbon Computing lately, but if they have it set up anything like the 1.6 G5 at Computer Systems Centre (Spadina+College) then I know what you mean. It too is a dual monitor setup, and they have every damned piece of shareware loaded up on the thing, with as much crap in the dock running as they could find. The real kicker is that they have one of those screensaver-on-your-desktop-background things running, and it's set to suck up as much CPU as it wants. Needless to say, everything is slow! Hell, dragging a window feels slower than my G4 400 with a Rage 128.

If you have time, go to Carbon again, and turn off all the crap to get it to resemble a stock machine as much as possible, and restart it. Run the apps that you usually run and I guarantee you it will feel infinitely faster.

Hope that helps. While I can't testify to the speed of a dual-monitor setup over the long run, I can tell you that demo machines are whored in general with every whiz-bang utility out there. And that can be a big factor. Good luck!

Ryan1524 · Sep 22, 2003, 03:54 PM

no, they're pretty clean actually. the dock contains about 8-10 apps only. and the only thing active was iTunes and FCP. whcih i turned off. but the lag continues. same for the PB. it's not like some stores where you have dozens and dozens of apps in the dock and they're all active.

ow, something i forgot to mentio, the 1.6 G5 was driving a 20" and an 18" Wacom Touch Screen LCD. buti can't see how it could affect performance..i mean it's only an input device.

Apfhex · Sep 22, 2003, 04:34 PM

Indeed, I run my 15" TiBook with a 19" Samsung CRT (@1280x960) and notice no performance drops, except for perhaps those CPU intensive screensavers that have no options to appear on only one monitor.

superlarry · Sep 22, 2003, 10:28 PM

no slowdown with dual displays on my powerbook 12" (867).
that G4/400 problem could be because enabling two separate displays might be too taxing on a video card - it might not've had enough RAM to keep quartz extreme enabled, and quartz extreme provides a heck of a lot of "snappiness". but i don't understand how this could be a problem on a G5 - even if there are a ton of "whiz-bang" programs running, OSX can handle that and keep things looking nice. my bet's on a hardware failure/overheating.