Index: src/wp-admin/css/dashboard.css
===================================================================
--- src/wp-admin/css/dashboard.css	(revision 46192)
+++ src/wp-admin/css/dashboard.css	(working copy)
@@ -999,6 +999,10 @@
 	word-wrap: break-word;
 }
 
+.dashboard-comment-wrap-no-avatar {
+	word-wrap: break-word;
+}
+
 /* Browser Nag */
 #dashboard_browser_nag a.update-browser-link {
 	font-size: 1.2em;
Index: src/wp-admin/includes/dashboard.php
===================================================================
--- src/wp-admin/includes/dashboard.php	(revision 46192)
+++ src/wp-admin/includes/dashboard.php	(working copy)
@@ -761,12 +761,20 @@
 
 		<li id="comment-<?php echo $comment->comment_ID; ?>" <?php comment_class( array( 'comment-item', wp_get_comment_status( $comment ) ), $comment ); ?>>
 
-			<?php echo get_avatar( $comment, 50, 'mystery' ); ?>
+ 			<?php
+ 			$show_avatars       = get_option( 'show_avatars' );
+ 			$show_avatars_class = 'dashboard-comment-wrap-no-avatar';
 
+ 			if ( 1 == $show_avatars ) {
+ 				echo get_avatar( $comment, 50, 'mystery' );
+ 				$show_avatars_class = 'dashboard-comment-wrap';
+ 			}
+ 			?>
+
 			<?php if ( ! $comment->comment_type || 'comment' == $comment->comment_type ) : ?>
 
-			<div class="dashboard-comment-wrap has-row-actions">
-			<p class="comment-meta">
+				<div class="<?php echo $show_avatars_class; ?> has-row-actions">
+				<p class="comment-meta">
 				<?php
 				// Comments might not have a post they relate to, e.g. programmatically created ones.
 				if ( $comment_post_link ) {
@@ -786,9 +794,9 @@
 					);
 				}
 				?>
-			</p>
+				</p>
 
-				<?php
+			<?php
 			else :
 				switch ( $comment->comment_type ) {
 					case 'pingback':