I am not running on any 1800's but know someone who just installed 3.0 on one. Given that the 1800 is all the same core components as the 1850, I cannot image there is a problem. The 1800's have an option for SATA drives - this is the only area of concern. If you have SCSI drives, then you shouldn't have any problems.
I have now specced the PERC 4/DC as it seems to be on the HCL for both ESX 2.5 and 3.0, better safe than sorry
Interestingly, in a seperate response to another post, I was told that ESX 2.5.3p3 even seems to see the embedded SATA controller and can use this, if the systen is specced that way.
i have run esx 2.5x on dell 1800's without any problem at all. HAvent tried esx 3.0 yet
The Dell 1800 will be added to the HCL once the certification has been completed
What about the HP ML350...
It is exactly the same drivers and hardware as HP ML370 and I have tested it both with ESX 2.5.x and 3.0.1 and it works great.
Are there any tests on HP ML350 ???