I have an old Compaq that has what is reported as a GeForce 4 MX on board GPU that Nvidia says uses the 96xx driver, but it doesn't work with that driver; terribly distorted screen. Using the 71xx legacy driver worked perfectly, while we still had it available. Has anyone tried building that legacy driver recently?
Did it work with the 96xx driver on older kernels? I wasn't working with kernels when the 71xx was dropped, but it may have been incompatible with the version of X that we have. Anyway, I will keep the 96xx driver as long as it builds, but gaining support for more modern hardware has to come first, as we are dropping a little behind.
No, always needed 71xx. Just because nvidia says a specific driver works with a given card does not make it necessarily so. Also there is a lot of overlap in nvidia drivers. The one released at the time the card was new is usually tuned to that card especially, and older cards may take a hit when the driver is updated for the new card. The newer the driver, and the older the card, the better the chance that adding support for a newer card has messed up something with the older card.
Card manufacturers also have a degree of latitude with tweaking the chips delivered by nvidia, to attempt to optimize their card for best performance. When nvidia upgrades a driver those individual tweaks are not taken into account, so a driver may work well with one brand of card and not another, even though they have the same basic chip. At the same time the older driver that was new when the card was built, and used to test the optimizations, still delivers top performance to the card that took the hit with the upgrade.
The problem with legacy drivers is that when nvidia decides to not upgrade the working drivers to build against newer kernels, either the card has to be replaced, or the user must decide to not upgrade the kernel any further. If a new version of xorg also gets a full rewrite, without a driver upgrade the battle to save the card is lost. Despite the best efforts of the open source developers, some cards just don't work with the open source drivers.