You can easily change the type of the virtual controller for a given disk.
Lets have a look at an example.

 

# Disk DescriptorFile
version=1
CID=fffffffe
parentCID=ffffffff
createType="twoGbMaxExtentFlat"
# Extent description
RW 4193792 FLAT "diskname-f001.vmdk" 0
RW 2097664 FLAT "diskname-f002.vmdk" 0
# The Disk Data Base
#DDB
ddb.adapterType = "ide"
ddb.virtualHWVersion = "3"
ddb.geometry.cylinders = "6241"
ddb.geometry.heads = "16"
ddb.geometry.sectors = "63"

The disk above uses a virtual ide-controller.

 

ddb.adapterType = "buslogic" This entry converts the disk into a SCSI-disk with BusLogic Controller
ddb.adapterType = "lsilogic"   This entry converts the disk into a SCSI-disk with LSILogic Controller
ddb.adapterType = "ide"   This entry converts the disk into a IDE-disk with Intel-IDE Controller

This changes the harddisk - but doesn't change the controller itself.

ide0.present = "TRUE"
ide1.present = "TRUE"
scsi0.virtualDev = "lsilogic"
scsi0.virtualDev = "buslogic"
scsi1.virtualDev = "lsilogic"
scsi1.virtualDev = "buslogic"

 

Use entries like this in your *.vmx file. By the way, you can have LSI-logic and BUS-logic controllers in one VM.

Think twice before you make changes like this with a boot-disk.

Bluescreen 07b - mass-storage driver:
Activate the apropriate driver in the registry: intelide.sys or vmscsi.sys or symmpi.sys - you may have to add files as well.

Black screen with cursor blinking in the topleft of the screen:
Write a new partition boot-sector.

You will need the vmware-vdiskmanager to do this - if you know any other method please let me know. Open the disk-descriptorfile with a text-editor like notepad. You will find something like

# Disk DescriptorFile
version=1
CID=fffffffe
parentCID=ffffffff
createType="twoGbMaxExtentSparse"
# Extent description
RW 4192256 SPARSE "ide-s001.vmdk"
RW 4192256 SPARSE "ide-s002.vmdk"
RW 4096 SPARSE "ide-s003.vmdk"
# The Disk Data Base
#DDB
ddb.virtualHWVersion = "3"
ddb.adapterType = "ide"
ddb.geometry.cylinders = "8322"
ddb.geometry.heads = "16"
ddb.geometry.sectors = "63"

We need the disksize in sectors so we have to sum up the size of all 3 pieces.
4192256 + 4192256 + 4096 = 8388608
Now use the vmware-vdiskmanager and run this command:
vmware-vdiskmanager.exe -c -s 8388608 -a buslogic -t 1 scsi.vmdk
Don't use a preallocated type of disk - because we don't need this disk later.

Open the file scsi.vmdk and take this lines

ddb.adapterType = "buslogic"
ddb.geometry.cylinders = "522"
ddb.geometry.heads = "255"
ddb.geometry.sectors = "63"

and replace the c/h/s entries for the ide-geometry with the scsi-values so that your descriptor-file looks like this:

# Disk DescriptorFile
version=1
CID=fffffffe
parentCID=ffffffff
createType="twoGbMaxExtentSparse"
# Extent description
RW 4192256 SPARSE "ide-s001.vmdk"
RW 4192256 SPARSE "ide-s002.vmdk"
RW 4096 SPARSE "ide-s003.vmdk"
# The Disk Data Base
#DDB
ddb.virtualHWVersion = "3"
ddb.adapterType = "buslogic"
ddb.geometry.cylinders = "522"
ddb.geometry.heads = "255"
ddb.geometry.sectors = "63"

Don't touch the CID or parentCID entries unless you know what you are doing!

Think twice before you make changes like this with a boot-disk.

Bluescreen 07b - mass-storage driver:
Activate the apropriate driver in the registry: intelide.sys or vmscsi.sys or symmpi.sys - you may have to add files as well.

Black screen with cursor blinking in the topleft of the screen:
Write a new partition boot-sector.