Is there a way to make AngularJS load partials in the beginning and not at when needed?

Yes, there are at least 2 solutions for this:

1. Use the script directive (http://docs.angularjs.org/api/ng.directive:script) to put your partials in the initially loaded HTML
2. You could also fill in $templateCache (http://docs.angularjs.org/api/ng.$templateCache) from JavaScript if needed (possibly based on result of $http call)

If you would like to use method (2) to fill in $templateCache you can do it like this:

$templateCache.put('second.html', '<b>Second</b> template');

Of course the templates content could come from a $http call:

$http.get('third.html', {cache:$templateCache});

Here is the plunker those techniques: http://plnkr.co/edit/J6Y2dc?p=preview

If you use Grunt to build your project, there is a plugin that will automatically assemble your partials into an Angular module that primes $templateCache. You can concatenate this module with the rest of your code and load everything from one file on startup.

https://npmjs.org/package/grunt-html2js

Add a build task to concatenate and register your html partials in the Angular $templateCache. (This answer is a more detailed variant of karlgold's answer.)

For grunt, use grunt-angular-templates. For gulp, use gulp-angular-templatecache.

Below are config/code snippets to illustrate.

gruntfile.js Example:

ngtemplates: {
  app: {                
    src: ['app/partials/**.html', 'app/views/**.html'],
    dest: 'app/scripts/templates.js'
  },
  options: {
    module: 'myModule'
  }
}

gulpfile.js Example:

var templateCache = require('gulp-angular-templatecache');
var paths = ['app/partials/.html', 'app/views/.html'];

gulp.task('createTemplateCache', function () {
return gulp.src(paths)
    .pipe(templateCache('templates.js', { module: 'myModule', root:'app/views'}))
    .pipe(gulp.dest('app/scripts'));
    });

templates.js (this file is autogenerated by the build task)

$templateCache.put('app/views/main.html', "<div class=\"main\">\r"...

index.html

<script src="app/scripts/templates.js"></script>
<div ng-include ng-controller="main as vm" src="'app/views/main.html'"></div>