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OneShot
06-13-2005, 10:55 AM
I'm have plan on getting a 2nd AL flat screen. Any warning that I should be aware?
Dual 2.5 G5 RAM 3.9.x ATI 9800XT 256mVram.
Software mostly used
Poser 6
LightWave 8.3

eblu
06-14-2005, 12:13 PM
yeah, two monitors invariably means that directly in front of you is the crack between the two monitors, so you actually have to crane your neck to see anything. I call that a caveat.

one nice thing is that LW is great on 2 monitors... one for Modeler and one for Layout.

Darttman
06-15-2005, 08:27 AM
From what I understand two monitors means the video card splits the on board memory to drive both, so a 128MB vid card would be using 64MB to drive each video monitor. How will this impact the view you use to model with? Hmm... any other thoughts.

Lightwolf
06-15-2005, 08:49 AM
...so a 128MB vid card would be using 64MB to drive each video monitor....
No quite. A frame buffer per monitor uses around (at 1280x1024) 5MB of memory. If you account for double, even tripple buffering it will be around 15MB. So the second screen (at that res) will use a max of 15MB extra (at that resolution). Everything else is used as geometry or texture memory and thus shared.
Mind you, the gfx board will also take a (very slight hit) due to more memory having to be read to refresh the display. at the res mentioned above, and 60Hz, the gfx board will use 5*60 = 300MB/s of bandwidth per monitor just to refresh the image.

Cheers,
Mike

monovich
06-15-2005, 11:56 AM
I just got a DVI KVM switcher so that I can switch my second LCD on my desktop (both 23" old school cinemas). So I have the first LCD as my main monitor on my G5, but I can switch the second one with the KVM to either be the main desktop for my PC, or it can be the second monitor for my mac.

this has pretty much revolutionized my workflow with LW. Even with the 23", I never had enough room to keep reference material up while I modeled. Now with thet second desktop on my mac, I keep my PSD files open over there, and work in LW on my main monitor. It's very handy.

I'm experimenting with putting LW panels and toolbars on the second monitor also, but I haven't completely gotten used to that yet.

The bar down the middle doesn't bother me at all. what does bother me is occasionally losing my mouse when the monitor is switched to the PC. I can't find which monitor it's on. :confused:

-steve

OneShot
06-15-2005, 04:57 PM
Has anyone heard of this problem :confused:

In some programs doing a single card w/ two monitors will screw up OpenGL rendering, because many render engines (and sometimes OpenGL in OSX) will get confused over which monitor has what addresses. This problem lies mostly in shadow and ray-tracing calculations.

Scazzino
06-16-2005, 09:33 AM
Has anyone heard of this problem :confused:

In some programs doing a single card w/ two monitors will screw up OpenGL rendering, because many render engines (and sometimes OpenGL in OSX) will get confused over which monitor has what addresses. This problem lies mostly in shadow and ray-tracing calculations.

No, exactly which program, doing what and which video card?

I've been using dual monitors since the Mac Plus believe it or not (It was a third party mod that enabled an external monitor, the Mac OS already had support built in for up to six monitors... ;-) and I've been using dual monitors on a single card ever since getting my first G4 MDD and now with the G5... Some software does have some window placement issues (LW moves the image viewer off the second monitor if you resize it, and it's on a secondary monitor to the left of the main monitor for instance) but I've never seen anything like what you're talking about...

Scazzino
06-16-2005, 09:38 AM
No quite. A frame buffer per monitor uses around (at 1280x1024) 5MB of memory. If you account for double, even tripple buffering it will be around 15MB. So the second screen (at that res) will use a max of 15MB extra (at that resolution). Everything else is used as geometry or texture memory and thus shared.
Mind you, the gfx board will also take a (very slight hit) due to more memory having to be read to refresh the display. at the res mentioned above, and 60Hz, the gfx board will use 5*60 = 300MB/s of bandwidth per monitor just to refresh the image.


That's not what the Apple System Profile says... it says that the VRAM is split in half... on my ATI Radeon 9800 Pro anyway...

ATY,R350:

Type: display
Bus: AGP
Display Type: LCD
Slot: SLOT-1
VRAM (Total): 128 MB
Vendor: ATI (0x1002)
Device ID: 0x4e48
Revision ID: 0x0000
ROM Revision: 113-A14401-117

Display:

Type: display
Display Type: LCD
VRAM (In Use): 64 MB
Resolution: 1280 x 1024
Depth: 32-bit Color
Mirror: Off
Online: Yes

Display:

Type: display
Display Type: LCD
VRAM (In Use): 64 MB
Resolution: 1920 x 1200
Depth: 32-bit Color
Main Display: Yes
Mirror: Off
Online: Yes

OneShot
06-16-2005, 12:13 PM
Cool '3D Mac Manic' thanks for the information. That's really helpful. I should have 128 on each with the 9800xt BTO VRAM 256. ;)

Scazzino
06-16-2005, 01:12 PM
If you are considering the Apple ACD 23", just make sure you get to check out the particular screen you are buying first... They have been known to have some color issues...

http://dreamlight.com/insights/bugs/hd23.html

OneShot
06-16-2005, 03:47 PM
I'm going to purchase a new aluminum DVI flat screen. I would have gotten it already but it's my wife B-day month. :eek:

So I'm waiting a few more weeks.

:mad: You got me a card and flowers! :mad: :o

:o :o :o :eek:

Lightwolf
06-17-2005, 03:17 AM
That's not what the Apple System Profile says... it says that the VRAM is split in half... on my ATI Radeon 9800 Pro anyway...

Hm, weird stuff and makes no real sense (unless the Radeon can't access a dual display like a large single display, which may affect 3D performance, especially if a 3D app window goes across both monitors).
Then again, it might just be an "infotmational" display with no connection to what is really going on.
You still have a slightly higher bandwidth usage with the second display though (not that it matters much with current gfx board bandwidths).
Cheers,
Mike