When I look at the settings in admin server info for PHP output buffering it shows 'no value'. Does this mean output buffering is off?

If you're looking in the phpinfo() output, then that means that PHP is configured not to do output-buffering automatically.

If you enable "GZip compression" in Admin->Configuration->GZip compression, then Zen Cart will attempt to enable output buffering itself while it serves its pages.

DrByte:

If you're looking in the phpinfo() output, then that means that PHP is configured not to do output-buffering automatically.

If you enable "GZip compression" in Admin->Configuration->GZip compression, then Zen Cart will attempt to enable output buffering itself while it serves its pages.

I have read some of your posts and you seem very knowledgeable on this subject. My question is - per your quote above - how do I get to those areas to make the adjustments. Before install my settings also read:

PHP Output Buffering (gzip) = OFF

Where do I go to turn it on? What is the true benefit?:D Thanks.

Only if you are on a dedicated/semi dedicated host where you can actually change the setting of the softwares installed on the server.

To turn it on post-install, you can set it in the Admin, as I mentioned above.

To turn it on pre-install, assuming you have control over your own php.ini settings, you can set it in php.ini or .htaccess. Since each host's setup is different, your hosting company can assist you in placing the setting in the right location that suits their server configuration.

In short, the buffering compresses content destined for the browser before transmission. This means that the page content might get delivered between your server and the customer's browser a bit faster than if buffering is not enabled. There's more to it than that, but that's the brief version. Lots more information can be read on the php.net website.