External video card

This product does what you ask but not on a G4 Mac; it requires USB3 and a min OS of 10.6.

http://eshop.macsales.com/item/NewerTech/VIDU3DVIA/

Most otehrs do not supoprt e Macs, only Windows. When I narrow the search and google "USB video adaptor mac" I get some hits but many require a minimum USB 2.0 port. Your on-board USB ports are USB 1.1 and would be terribly slow at delivering video signals. You would have to add the expense of a PCI USB adaptor ard to the total cost.

I think you would do better to look for a reaplcement video card. There are still used/pulled ones about that work.

If you tell us which of the various PowerMac G4 version you have, we can help you search. If you give us a rough ideqa of where you are. Not much sense in one of us pointing you a link to a vendor that does not ship to your part of the world.

Also please read this, the best resource on Mac video cards:

http://www.jcsenterprises.com/Japamacs_Page/Graphics_Cards.html

Many later MDDs had the ATI Radeon 9000 64MB video card, a decent if not "blow your socks off" performer. A lot of perfectly good 9000s were pulled and replaced by faster video cards. That means the 9000s are not too hard to find on the used/pulled market considering the age of the computer.

I would search for "mac radeon 9000 agp" on auction and used parts sites. I just did so and found this close to the top of the list:

http://www.amazon.com/Apple-Radeon-9000-Video-Power/dp/B004574LBI

Cheaper than most external adaptors even if they worked.

http://www.ebay.com/itm/ATi-Radeon-9200-128mb-AGP-Graphics-Video-Card-Apple-Powe rMac-G4-G5-DVI-VGA-/251824836820?pt=LH_DefaultDomain_0&hash=item3aa1ee10d4

http://www.ebay.com/itm/nVidia-Geforce-4-Ti-4600-128mb-AGP-Video-Card-For-Apple- PowerMac-G4-DVI-VGA-/252036534989?pt=LH_…

mmost of those "Mac" video cards are really originally PC versions with the ROM flashed, so the typical connections will be VGA DVI. If you have an ADC monitor then you will have to look harder for an original Mac video card with the appropriate connector, or use one of those special adapters to hook an ADC monitor to a DVI port. I think it was called the DVIator from Dr Bott.

IF you want to test the ADC output, you can use a VGA monitor with this adapter

http://www.ebay.com/itm/1pcs-ADC-to-VGA-for-Apple-Power-Mac-G4-G5-Adapter-/11158 5141589?hash=item19fafe2355

or a DVI monitor with this adapter

http://www.ebay.com/itm/1pcs-ADC-to-VGA-for-Apple-Power-Mac-G4-G5-Adapter-/11158 5141589?hash=item19fafe2355