Check the following items:
– Configuration
– Layouts
– Block HTML output
– Translations
Uncheck the following items:
– Collections Data
– EAV types and attributes
-Web Services Configuration

2) Enabled APC

3) Magento needs much more memory than any other PHP scripts, so add more memory if possible.

In the php.ini file set php_value memory_limit 128M
this will make a huge improvement on performance.

4. MySQL Cache Size

Configure or ask your hosting company to switch on or tweak to ensure you have enough mysql cache. I have found the following to be a good reasonable size:
query_cache_size=64M

5. Optimize the size of images, swf, include external js into one file, use css @import for external css and don’t include extra css.

6) Remove Home Page Elements

Goto Magento Admin -> CMS -> Manage Pages -> Home -> Custom Design

The “Layout Update XML” box is pre-populated with functions and calls, all of which can be removed without any apparent problems.

Above modifications and updates will surely improve the performance of your Magento eCommerce website.