This is a C test program which reproduces the problem.
Rename it to scrolltest.c, then compile with:
cc -O scrolltest.c
./a.out will print numbers faster and faster, with the number representing a delay between prints.
At some point, usually between 100,000 and 300,000 (on a 2.26 GHz P4), the xterm locks up if the nvidia driver is used, but not if the nv driver is used.
Garbage appears in all or some of the xterm at the time of the crash. Sometimes all but the last text line is garbled.
If it makes it all the way down to 1, then the test has passed.
It seems like a timing issue. Perhaps the GA-8IHXP is not able to handle fast bus transactions, isn't supplying enough power to the card, or there is a software race condition.
AGP is disabled (see XF86Config).
No overclocking or "turbo" options are on -- just BIOS performance defaults. However, there might be some GA-8IHXP chipset setting which needs to be used with the nvidia card.
Main memory is 1GB of 1066 RIMM.
The main power supply is fine (550 W Antec).
No other problems appear on the system, and this problem of X crashing on fast scrolling or movement nearly goes away with the nv driver, leading me to suspect at first that these problems are closed-source software bugs.