A few days ago I told you that NVIDIA will announce a new professional graphics cards family based on GeForce4 architecture and known as Quadro4 only in April (see this news story). Nevertheless, it is already possible to get a Quadro4 today. The method I am going to tell you about is based on the fact that Quadro4 solutions, just like in case of all the other Quadros, will be built using the same GeForce4 chips. The differences between Quadro4 and GeForce4 will be only in the driver support. That is why all you need to do to install the Quadro4 drivers for your GeForce4 graphics card is to change the chip ID.

As we managed to find out, the chip ID is set in two places on the graphics card. On the front side of the card made following the reference design there are two 10kOhm resistors (marked yellow on the picture):

There are three spots on the pi marked with "0", "1" and "2". We managed to get the following working resistor combinations:

• If one resistor stands in "0" position, another one – in "2" position, then the card is identified as GeForce4 Ti4600.
• If one resistor stands in "0" position, another one – in "1" position, then the card is identified as GeForce4 Ti4400.
• If there is no resistor in "0" position, and one resistor only in "1" position, then the card is identified as GeForce4 Ti4200.

On the reverse side of the card there is a more interesting layout bit:

On the reference GeForce4 Ti4600 card the 10kOhm resistor is set into "A" position. If you move it to "B", then the card will be identified as NVIDIA Quadro4 900XGL. As a result, the GeForce4 Ti4400 card obtained from GeForce4 Ti4600 as described above, will turn into NVIDIA Quadro4 750XGL, and NVIDIA GeForce4 Ti4200 – into NVIDIA Quadro4 700XGL.

We really felt sorry for the card, which had to undergo so many transformations that is why we provided it with a set of jumpers. So now, we can play on our NVIDIA GeForce4, and the next minute work on NVIDIA Quadro4. This has become as easy as ABC. :)