The "unable to load library steamclient64.dll" error is almost never a sign of hardware failure. In 90% of cases, it is caused by a zealous antivirus deleting the file or a corrupted Steam update.
This DLL often relies on specific Microsoft libraries to run. Missing or corrupted redistributables are a common culprit. unable to load library steamclient64.dll
Wait for a terminal window to open and close, then try launching Steam again. 6. The "Clean Reinstall" (Last Resort) The "unable to load library steamclient64