Data Transfer Rates Vs. I/O Performance
Data transfer performance is actually an interesting aspect of the comparison of PCI-X and PCI Express; the numbers do not differ very much between the two. Running a RAID 0 array with as many as eight drives will not even get you close to the maximum bandwidth that either PCIe x4 or PCI-X 133 can offer. So is there any reason to go for a PCI Express controller card, even though they lack an obvious benefit and even come at higher prices?
Yes, there is. We intentionally picked the RAID controller test bed to compare two almost identical cards in the identical, every day environment. As you read on, you will notice that PCIe actually does offer some improvement when it comes to I/O performance.