Network Controller (Wireless)
Ethernet Controller (LAN)
PCI Simple Communication Controller (Card reader)
So, you will notice you would not be able to use your wireless, wired connection (LAN) and Card Reader Slot. So here is the drivers you will need: (for both Windows 7 32-bit and 64-bit)
Most E1-531 uses Atheros Wireless drivers, but there are some models that uses broadcom or Intel Wireless device. Install according to your secification or test which work for you.
Atheros AR9xxx/AR5xxx Wireless Driver : Download
Broadcom 802.11 Wireless Driver : Download
Intel Centrino Wireless-N 105 Driver : Download
LAN - Ethernet Controller
Broadcom Netlink (TM) Gigabit Ethernet Controller
Broadcom Card Reader Driver
That's all what you need and now after the installation your laptop will have all the drivers it need. If you need to update to the latest drivers, just simply go to Nvidia for your graphic, Intel for your graphic, chipset and USB and Realtek for your audio drivers. You will see "Automatically update" on each website (except realtek) and let it scan and suggest the latest drivers available for you laptop. Anyway, there are no significant improvement by installing the latest drivers, I will only update my drivers if there are bugs with the current drivers.