PowerEdge 840 - Windows Server 2008 R2 - Can´t update drivers

Hi everyone,  I have a PowerEdge 840 running Windows Server R2.

Sorry for my ignorance. I am new with Servers. I am intern in IT´s company and my co-worker asked me to install Windows Server 2008 R2 and after update the drivers.

I downloaded OpenManage Server Administrator and could not update the drivers. 

Surfing on the internet, I found a ebook, which explains how to install drivers with OpenManage Essentials. I was able to downloaded the latest catalog drivers, but I can´t find the devices on OpenManage Essentials, so I was not able to update drivers by Essentials.

I tryed through Dell Support. I downloaded the driver for Windows Server 2008 R2, but when I was installing, some message showed: This driver can´t be installed on this OS and the installation was cancelled. This for all drivers on Dell Support.

Someone has some idea for updating drivers??

Thanks so much.

Gustavo