Yes, 2012 needs drivers, and the only way to get them out of the EXE is to run the EXE to extract the contents (or use some other extraction tool).
If you don't have a Windows machine (and/or you are not able to do it from a Linux/Mac box), don't have a Windows virtual machine you could extract it in, AND you have access to Server 2008 (non-R2), then you can install with that long enough to get the driver extracted, as the PERC 4 drivers are native to 2008 (but not later versions).
Since Dell does not support 2012 on the 8G servers, you will need to use the Server 2008 R2 drivers:
http://www.dell.com/support/drivers/us/en/19/DriverDetails/Product/poweredge-1850?driverId=9K3D3&osCode=WS8R2&fileId=2731109791 (you need the 'hard drive' version)
The onboard RAID controller for the 1850 (PERC 4e/Si) does NOT support non-RAID, so in order to use the disks individually, you would need to set up each disk as a single-disk RAID 0. An alternative would be to disable RAID altogether, which uses only the SCSI controller onboard. The RAID cache will no longer be usable with RAID disabled though.
You configure RAID in the CTRL-M utility (during POST). You disable RAID in the BIOS Setup (F2), under Integrated Devices (CTRL-M will no longer be accessible when disabled - you will use CTRL-A to see the disks).