Edwin van der Heide

i have just made a strange experience working on an intel mini mac we 

i was planning to run the machine without a display connected as its 

output is only sound and dmx with another part of the patch doing 

jitter video processing of a live camera feed.

in such a situation i use a VNC server to be able to operate the 

this works flawlessly when an actual screen is connected to the mini 

if i unplug the screen, though, and reboot without a display the 

jitter performance drops from 30 fps to 5 fps.

now, if i do the same to a PPC mini mac the same thing happens, but 

the frame rate drops from 11 fps to 7.5 fps, so that in the end the 

PPC outruns the intel machine (!) which is actually 3 times as fast.

as far as i understand it the intel machine does not have any 

dedicated video ram anymore, but uses a part of the computers memory.

presumably the size of memory changes depending on the size of the 

display and without an actual screen there, it could be very small.

could i fool the intel machine that there really is a nice 20 inch 

i have just made a strange experience working on an intel mini mac we  
use for an installation.

i was planning to run the machine without a display connected as its  
output is only sound and dmx with another part of the patch doing  
jitter video processing of a live camera feed.

in such a situation i use a VNC server to be able to operate the  
machine remotely.
this works flawlessly when an actual screen is connected to the mini  
mac.
if i unplug the screen, though, and reboot without a display the  
jitter performance drops from 30 fps to 5 fps.

now, if i do the same to a PPC mini mac the same thing happens, but  
not quite as bad.
the frame rate drops from 11 fps to 7.5 fps, so that in the end the  
PPC outruns the intel machine (!) which is actually 3 times as fast.

as far as i understand it the intel machine does not have any  
dedicated video ram anymore, but uses a part of the computers memory.
presumably the size of memory changes depending on the size of the  
display and without an actual screen there, it could be very small.

could i fool the intel machine that there really is a nice 20 inch  
screen there somewhere..?

intel-experience

Usually the problem is with the machine not wanting to run at all, 

and the solution for that can sometimes be to hook a video adapter 

onto the machine to trick it into thinking it has a display. This 

seems like something different, but it's still worth a try.

> i have just made a strange experience working on an intel mini mac 

> i was planning to run the machine without a display connected as 

> its output is only sound and dmx with another part of the patch 

> doing jitter video processing of a live camera feed.

> in such a situation i use a VNC server to be able to operate the 

> this works flawlessly when an actual screen is connected to the 

> if i unplug the screen, though, and reboot without a display the 

> jitter performance drops from 30 fps to 5 fps.

> now, if i do the same to a PPC mini mac the same thing happens, but 

> the frame rate drops from 11 fps to 7.5 fps, so that in the end the 

> PPC outruns the intel machine (!) which is actually 3 times as fast.

> would anyone know a way to explain this?

> as far as i understand it the intel machine does not have any 

> dedicated video ram anymore, but uses a part of the computers memory.

> presumably the size of memory changes depending on the size of the 

> display and without an actual screen there, it could be very small.

> could i fool the intel machine that there really is a nice 20 inch 

Usually the problem is with the machine not wanting to run at all,  
and the solution for that can sometimes be to hook a video adapter  
onto the machine to trick it into thinking it has a display.  This  
seems like something different, but it's still worth a try.

> hi!
>
> i have just made a strange experience working on an intel mini mac  
> we use for an installation.
>
> i was planning to run the machine without a display connected as  
> its output is only sound and dmx with another part of the patch  
> doing jitter video processing of a live camera feed.
>
> in such a situation i use a VNC server to be able to operate the  
> machine remotely.
> this works flawlessly when an actual screen is connected to the  
> mini mac.
> if i unplug the screen, though, and reboot without a display the  
> jitter performance drops from 30 fps to 5 fps.
>
> now, if i do the same to a PPC mini mac the same thing happens, but  
> not quite as bad.
> the frame rate drops from 11 fps to 7.5 fps, so that in the end the  
> PPC outruns the intel machine (!) which is actually 3 times as fast.
>
> would anyone know a way to explain this?
>
> as far as i understand it the intel machine does not have any  
> dedicated video ram anymore, but uses a part of the computers memory.
> presumably the size of memory changes depending on the size of the  
> display and without an actual screen there, it could be very small.
>
> could i fool the intel machine that there really is a nice 20 inch  
> screen there somewhere..?
>
> any pointers would be appreciated!
>
>
> many thanks
> hiaz
>


> could i fool the intel machine that there really is a nice 20 inch  
> screen there somewhere..?

try this
http://tvtool.info/english/dummy_e.htm

I did a web-search: running OSX headless. These two might be of interest:

http://hoeben.net/aldo/the_headless_horserider_er_mac_mini

http://www.macfixit.com/article.php?story=20030623083303282

The dummy adaptor idea seems rather clever and might work on a MacTel.

(As for VNC servers imposing extreme CPU loading, I've had similar 

experiences under Win2K/XP in a server application (not a Max app -- 

this is the day job) with a VNC server taking better than 50% of a 2.8G 

P4 (and not related to headless ops, per se). We never resolved it, and 

now I wonder if it was something as silly as the monitor having been 

I did a web-search: running OSX headless.  These two might be of interest:

http://hoeben.net/aldo/the_headless_horserider_er_mac_mini
http://www.macfixit.com/article.php?story=20030623083303282

(As for VNC servers imposing extreme CPU loading, I've had similar 
experiences under Win2K/XP in a server application (not a Max app -- 
this is the day job) with a VNC server taking better than 50% of a 2.8G 
P4 (and not related to headless ops, per se). We never resolved it, and 
now I wonder if it was something as silly as the monitor having been 
turned off!)


On 1 Dec 2006, at 23:56, jennek geels wrote:

>> could i fool the intel machine that there really is a nice 20 inch 

thanks a lot for the pointer to the TV dummy.

I have soldered up 2 yesterday and they work brilliantly!

>
> On 1-dec-2006, at 23:05, hiaz wrote:
>
>> could i fool the intel machine that there really is a nice 20 inch  
>> screen there somewhere..?
>
> try this
> http://tvtool.info/english/dummy_e.htm
>
> HtH
> -jennek

This is a rather reply, but...
thanks a lot for the pointer to the TV dummy.

intel experience