Manual vs. cron Drupal Update run

Would it be possible to disable the cron driven Drupal Update and have a manual button instead?
Our ISP's setup is giving us problems with cron caused MySQL time-outs during high traffic times that effectively block the Drupal cron jobs (triggered by poorman's cron). I disabled Drupal Update and have had no problems since. I would love not having to enable/disable the module every time I want to check for updates.
I would welcome any alternative suggestions and hacks.