PCI card in slot 4 maybe bad. Be advised the IDRAC may not report of a part in slot 4, probably because the part is bad and not registering. A TSR and dset could not report the anything for the slot in question to aid in identifying the issue or the part in the slot.
Physically on the system is the only sure fire way of identifying the part however if the system is located elsewhere more than likely the component is a NVRAM/MARVELL/ADPT/W2PWA/Controller Quest part number 5KVY3 equivalent to Dell part number WG0YW
Try reseeding the part or moving it to another slot if possible as part of troubleshooting. Also attempt a power down recycle sequence
1. Power down
2. Unplug power cord
3. Hold down power button for 10 seconds
4. Plug in power cord
5. Power up