Hi,
Please DO remember that you CANNOT store VM's on an IDE disk! You will need SCSI somewhere, even for a whitebox. Only SCSI, iSCSI and NFS is supported for creating VMFS filesystems where the VMs must be sitting. That is exactly why people buy the SAS board: You can connect SATA to it, and it reports the disk(s) as being SCSI....
You can get around this issue, and that is by installing an NFS server inside the service console. On the forum here there are some posting about the topic. In that case you would store your VMs on an NFS, which happens to be local to your system. It is not great for performance, but it works.
And I would not call the SAS board a "bad performer", it is just that the onboard controller is crippled in cache. For less money you buy a "cheap" mainboard with a separate LSI SATA controller, which will perform better.