Clarify PCIE 4X slots type ML350. G5

[DaveyH]

Proliant ML350 G5.   395566-003 MB  Win server 2008 R2.  There are 3 short black slots marked PCIE 4X and 3 white PCI-X slots.   The black slots have a short section first followed by a much longer section after the notch.   The PCIE 4X cards available seem to be the reverse -  longer section first but still shorter than the long section on the black slot.   I would like to put a USB card in one of these slots (the onboard is mostly usb 1.1  and when you insert stuff it says device not recognized usually).   Are these slots an outdated version of the PCIE?  I have seen one USB 3.1 card with the short front slot but the longer section is still shorter than the slot it would go in.  The rest have the long slot first so they certainly won't fit.   Not sure what to look for.  I think the notches maybe distinguish 3..3V from 5V?  Clarification appreciated.   The PCI-X 133 slot has an unused scsi card (maybe was for a tape backup) which I plan to remove and try an old Soundblaster card.   That leaves the 2 PCI-x 100 slots.  I have a double notched usb card that says it is PCI but the notches don't line up.  

[Ravi2019]

Hello Mr

As this old generation i can share you the link which help you to know the status of the PCI feature.

https://h20195.www2.hpe.com/v2/GetPDF.aspx/c04284193.pdf - Page 5 

https://h10057.www1.hp.com/ecomcat/hpcatalog/specs/provisioner/05/458243-421.htm

Form Factor Notes 
6 PCI Express x4 x8 15 StandardHeight/Length
5 PCI Express x4 x8 6 StandardHeight/Length
4 PCI Express x4 x8 9 StandardHeight/Length
3 64-bit /100MHz PCIX NA NA 12 StandardHeight/Length  PCI-X 100MHz
2 64-bit /100MHz PCIX  NA NA 12 Standard  Height/Length PCI-X 100MHz 
1 64-bit /133MHz PCIX  NA NA 20 Standard Height/Length PCI-X 133MHz

Thank you

Ravi swamy 

HPE