dual-head PCMCIA videocard

[zver17]

does anybody have any experience with using these in a T42 (with Radeon9600)? I would like to connect 2 external monitors to the TP, and use extended desktop over 3 screens (including the TFT) to get lots of real estate (I do lots of coding/visualisation). any past experience or suggestions would be appreciated!

[RonS]

I know a lot about this. I can run up to 12 monitors (possibly more) off my Thinkpad. Your Thinkpad (running 98 or XP) already supports two simultaneous displays. You need to add one more, or two if you want to run all DVI.

You have at least four options:

1. Use a PCMCIA video card. There are two you should look at. 1) The display-to-go from Margi.com. These have been discontinued, but are available from e-bay. 2) The VillageTronic.com VTBook adapter. I have both. The Margi card is better, but the VTBook supports DualHeaded operation off of one PCMCIA card.

2. Get a docking station and put a PCI-based video card in it. I run a Radeon 9250 in the dock. This is straightforward, and the highest performance option you have. You could also run a 4-headed or 8-headed video card in the dock, but you may have to tweak the BIOS to get it going.

3. You can extend your desktop the the screen of another computer (like an old notebook computer) via an ethernet connection. Look at www.maxivista.com - they have a program called MaxiVista that is fantastic. (I was a beta tester on that program.)

4. There are some new USB-based video adapters out there. I imagine that they're pretty slow, but I've never tested them.

[zver17]

wow - thanks for the very detailed info.

I have tried maxivista and its a great cheap solution, which I will use in the interim. the only annoying thing is the need to have an actual cpu-box attached to the monitor (for obvious reasons, of course). for the moment i've found an old crappy celeron small factor form so am using it is a monitor stand. the video card in it seems a bit poor, as the display is a flickery (very visible when using the celeron directly, but somehow less visible with maxivista).

I am also weighting up the PCMCIA option. When you say "VTBook supports DualHeaded operation off of one PCMCIA card" you mean I could attach 2 external displays to it (plus another through the T42 VGA, plus the T42 itself, making a total of 4 displays? - the vtbook web specs read a bit vague to me in this respect).

also, why do you think the margi card is better? Some sites suggest it doesnt fully support winXP (disables hibernation?)

[RonS]

The VTBook now supports dual-headed operation, so yes - you could have a total of 4 displays off of your Thinkpad. See www.villagetronic.com for info about the dual-headed feature, but I haven't tested it.

The Margi card supports hibernation, the VTBook does not. It's frusterating to come into the office in the morning and the only monitor still glowing brightly is connected to the VTBook card. I've contacted VillageTronic support about this several times, but they never responded., although they have been good to respond to other problems.

The VTBook claims to be faster, but when run against standard 2D benchmarks the Margi card does better under Windows. If you want to run 3D apps, the VTBook would trash the Margi card but neither could ever compete against a real video adapter.

The VTBook seems to draw more power, definitely runs hotter, and has a bulky end connector that means you can only run one at a time. The Margi card uses a pigtail to bring the connector away from the PCMCIA slot, so you can run other cards next to it without worry.

[zver17]

thanks again Ron,

when you say 'neither could compete with a real video card' you mean a desktop-type video card installed in the dock II PCI slot? Incidentally, would there be any dock-based constraints on the performance of this card, eg, if I got a 256mb card? I presume in any case any slowness would apply to the external-card-display only, so I would be better off running the demanding graphics on the laptop screen or the built-in VGA screen, leaving the PCMCIA for less demanding displays. I dont do 3D graphics, at least at the moment, so this is probably not a big deal.

Incidentally, have you been able to run the margi card simultaneoulsy with the lacie firewire800 card in the T42 PCMCIA slot (ie, do they physically get in each others way)?

[gazingwa]

If you don't do 3d, don't worry about the memory, the only constraint is pci, there is no agp slot, get a matrox dual head card for the dock, they are the best for 2d and they do very well with multiple monitors.

[RonS]

Yes, I meant that neither the Margi or the VTBook can compete with a real video card installed in a PCI, AGP or PCIe slot. The only real contraints in the second (real) video card performance are:

1) When moving a window from the primary adapter to the secondary adapter (or back), data is moved across the PCI (or AGP) bus, causing a slight slow down in performance. Barely noticable, except on the PCMCIA video cards where it can be very noticable. Note that when a window is moved back and forth between two monitors on the same physical adapter, everything happens in local video memory so it's very fast.

I noticed something strange lately: I installed a screen saver that uses (I think) Direct3D. When undocked, it runs fast. When docked with the second video adapter in the Dock (the ATI 9250), it runs slow. I think there must be something about Direct3D performance when two video drivers are running. I'm not sure. The screen saver was running on the primary monitor with the FireGl T2 (aka Radeon 9600).

Getting extra memory on the second video card will probably be a waste. 64MB should be fine. I picked up one with 128MB because it was the same price.

You have the right idea: use the third (and fourth) monitors for less demanding displays.

Yes, I've run the LaCie firewire card and the Margi card at the same time. No problem.