PE2850 Memory/battery Issue detected

So no way to test it to be sure?

You can put it in the system memory slot and run diagnostics, but if you are getting a memory/battery error, no amber LCD, and your OS mysteriously won't boot (and you can't repair it), then you need to replace the memory (small chance it could be the riser which contains the memory DIMM for the PERC).  Many people attempt to fix the ntldr (or other similar messages), but they won't be successful in this situation - knowing what you now know, don't try a repair - it won't work and may actually break your OS.

If you were getting a voltage message on the LCD and the OS booted ok (or simply needed repair, which succeeds), then the battery needs replacing.  The riser may be to blame here as well, but again it is rare.

"Just replaced the memory still had the error until I rebooted again."

This CAN be a normal error.  Any time the RAID cache becomes corrupted or lost (power out for extended time, battery failure, etc.), you can get that message.  If it consistently returns on every boot, then that is a problem.

"Still getting the ntoskrnl.exe error going to try and repair that."

Yes, the possibility of OS corruption still exists (writes stored in the cache that was lost were never committed to disk, so files may have been in a critical state when the cache was lost), so repairing the OS is the next step if it still won't boot.  With the memory/battery issue resolved though, it is only now possible to explore repairs of the OS.

Just replaced the memory still had the error until I rebooted again. Still getting the ntoskrnl.exe error going to try and repair that.

Replace it "hot" ... do NOT power down to replace it - just pull the old/failed drive, wait 60 seconds, insert new drive.  Depending on the drive and the state of the array, it will probably start rebuilding automatically.  If not, then you will need to assign it as a hot-spare to initiate the rebuild.

Now I got a failed drive.... seems like one thing after another is happening :emotion-12:.Whats the procedure for replacing a failed drive on the Perc 4e/di? Its just a raid 1 array

If it is a RAID 1, you replaced the disk, and assigned it as a hot-spare, and it has not started rebuilding, you may have a problem with your array - the controller can't make a complete copy of the virtual disk to the new drive, so it doesn't even try.  Is the new disk for SURE compatible (make/model, size, etc.)?

I already have one set to hotspare but it didnt automatically rebuild it. Guess I need to find some instruction been a min since I played with the raid controller.

I havent removed the bad disk yet I had a hot spare that's just been sitting in the server just in case one failed.