Convert ide disk to scsi

I p2v a PC with IDE drive controller to a virtual machine on the ESX 4. In the convert procedure,the "driver controller"  configuration is "preserve source".of course,the VM would not start up on the esx server,because esx server can only support SCSI controller.

In order to make the vm start up.I convert the ide disk to scsi one in my own way,and finally this vm start up.all seems goes ok .but  when i shutdown the vm ,the latency is very long. Does the latency somewhere result from the way i convert the disk?

here is the method I convert the disk:

Modify the *.vmx file

replace thes directive :

ide0:0.present ="TRUE"

ide0:0. fileName="vmdisk.vmdk"

....

（all the directive about the ide0:0）

with these:

scsi0.present = "TRUE"

scsi0.sharedBus = "none"

scsi0:0.present= "TRUE"

scsi0:0.fileName = "vmdisk.vmdk"

scsi0:0.deviceType = "scsi-hardDsik"