I'm having a similar problem with my ATI X800XL -
logdump follows:
2005-10-12 18:12:27 ATITool v0.24 started.
2005-10-12 18:12:27 Detected GPU Chip: R430 (554D), 16 Pipelines, 256 MB
2005-10-12 18:12:27 Temperature monitoring: not supported
2005-10-12 18:14:36 Scan for Artifacts started... Core: 398.25 Mhz Memory: 492.75 Mhz
2005-10-12 18:14:36 Scan for Artifacts running for: 0:00:00
2005-10-12 18:14:40 Scan for Artifacts stopped Total runtime: 4 seconds
2005-10-12 18:31:53 Application terminated.
2005-10-12 18:32:18 ATITool v0.24 started.
2005-10-12 18:32:18 Detected GPU Chip: R430 (554D), 16 Pipelines, 256 MB
2005-10-12 18:32:18 Temperature monitoring: not supported
2005-10-12 18:36:38 Application terminated.
2005-10-12 18:36:41 ATITool v0.24 started.
2005-10-12 18:36:41 Detected GPU Chip: R430 (554D), 16 Pipelines, 256 MB
2005-10-12 18:36:41 Temperature monitoring: not supported