检索产品并对Magento进行分类

I'm having a problem with my code currently it's loading the products but not accepting the order filter. here is what I have. Would appreciate any help.

 $_productCollection->clear()
               ->setOrder('entity_id', 'DESC')
               ->setPage($_GET['pageNo'],12)
               ->load()
               ;

Hello check below code

$collection = Mage::getModel('catalog/product')->getCollection();

$collection->setOrder('entity_id', 'DESC');

$products = $collection->load();