Update - i didn't actually test with a different USB, and Lion randomly shut off during the install, and when I tried to boot it again, it was going at slow DVD speeds, and with those kinds of speeds, OS X would take hours to install, assuming my USB failed, trying with a different one now.

EFI.zip

Our former EDP utility having long been abandoned, here are full packs for the Latitude D620/D630 series. The packs do not require any subsequent tuning at all, they provide everything required to obtain a fully working system (CPU power management, graphics, LAN, audio, keyboard, trackpad), non-OOB wireless, bluetooth and any other devices excluded of course.
 
However, some manual tuning for proper Sleep/Wake operation is required: setting hibernation mode to plain old sleep and deleting any eventual sleepimage file. This is done through the following Terminal commands upon final OS X installation:

sudo pmset -a hibernatemode 0
sudo pmset -a hibernatefile /dev/null
sudo rm -f /var/vm/sleepimage

Vanilla support stops at Lion 10.7.5 for all Intel GMA based models and the D620 nVidia due to GPU support limitations in Mac OS X. For those systems, ML may be installed and tuned back to 32bit operation through MLPF hack. Look at the Dell installation guides forum subsection for MLPF'ed ML guides and packs. It's not 100% bug-free though... Only the D630 nVidia supports vanilla installation of OS X Mountain Lion / Mavericks / Yosemite / El Capitan and Sierra / High Sierra (macOS only with Penryn CPUs). For all models, read the Performance tuning thread for CPU + GPU tuning if required but the FakeSMC kext included in the packs below brings it all.


D620 GMA950 LoRes (WXGA 1280x800):
D620_GMA950_LoRes_10.6.8_Pack.zip     D620_GMA950_LoRes_10.7.5_Pack.zip
 
D620 GMA950 HiRes (WXGA+ 1440x900):
D620_GMA950_HiRes_10.6.8_Pack.zip     D620_GMA950_HiRes_10.7.5_Pack.zip
 
D620 nVidia Quadro 110M (all res):
D620_NV110m_10.6.8_Pack.zip     D620_NV110m_10.7.5_Pack.zip
 
D630 GMA X3100 LoRes (WXGA 1280x800):
D630_X3100_LoRes_10.6.8.zip     D630_X3100_LoRes_10.7.5_Pack.zip
 
D630 GMA X3100 HiRes (WXGA+ 1440x900):
D630_X3100_HiRes_10.6.8.zip     D630_X3100_HiRes_10.7.5_Pack.zip
 
D630 nVidia Quadro NVS 135M (all res):

D630_NV135m_10.6.8_Pack.zip   D630_NV135m_10.7.5_Pack.zip

D630_NV135m_10.8.5_Pack.zip   D630_NV135m_10.9.5_Pack.zip

D630_NV135m_10.10.5_Pack.zip   D630_NV135m_10.11_Pack.zip

D630 nVidia Quadro NVS 135M + Penryn C2D CPUs (all res):

D630_NV135m_10.12_and_10.13_Pack.zip

NB: MyHack highly recommended for installation of Snow Leopard, Lion, Mountain Lion and Mavericks. Use myHack v3.3.1, except for SL which requires v3.1.2 (there's a bug related to SL in v3.3.1). For Yosemite and beyond, we recommend manual USB installer creation using instructions that have been detailed in numerous guides posted here.

NB: For Chameleon-based Yosemite installations (i.e. no Clover or otherwise), not all kexts load from /E/E. Eg: VoodooHDA + HDADisabler or lspcidrv. In such cases, copy the kexts to /L/E, repair permissions and rebuild the cache with the following Terminal commands:

sudo chmod -R 755 /Library/Extensions
sudo chown -R 0:0 /Library/Extensions
sudo touch /Library/Extensions
sudo kextcache -Boot -U /

Update to Chameleon r2468 is recommended for proper hardware support such as good CPU detection.

Chameleon-2.3svn-r2468.pkg.zip

NB: For Enoch-based Yos/EC/Sierra installations (recent Enoch versions such as r2795 and beyond for instance), you may use a kernel.plist file in /Extra with parameter KernelBooter_kexts set to Yes to load kexts from /E/E directly. Those kexts will not natively be considered for prelinked kernel/kext cache generation so boot time will be a little slower. To maximise boot time, you can either move kexts from /E/E to /L/E or copy them from /E/E to /L/E and set KernelBooter_kexts to No. You will then repair permissions and rebuild the cache as detailed above.

macOS Sierra and later can only be installed on D630 nVidia models fitted with a Penryn FSB800 C2D CPU (e.g.: T6xxx, T8xxx, T9xxx).

Enoch-rev.2839.pkg.zip

To answer a recurring question, here are BIOS settings that are known to work on D630 with Intel Crestline X3100 and nVidia Quadro NVS 135m GPU under Snow Leopard, Lion, Mountain Lion, Mavericks, Yosemite, El Capitan, Sierra, High Sierra, Mojave and Catalina (nVidia models only for Mavericks 10.9 and above). These settings were tested and verified with BIOS A16, A17, A18 and A19.

Onboard Devices:
. Integrated NIC = enabled
. Internel modem = enabled
. External USB ports = enabled
. Parallel port = ECP
. Serial port = COM1
. PC Card and 1394 = enabled
. SATA Operation = AHCI
. Module Bay Device = Enabled
. Flash Cache Module = Off
. ASF Mode = Off
. Microphone = Enabled
Video:
. Ambient Light Sensor = Off
. Brightness = max
. Brightness (AC) = max
. Primary Video = Onboard Video
Security:
. Admin Password = not set
. System Password = not set
. Internal HDD PW = not set
. Password Change = Permitted
. Password Bypass = Off or Reboot & Resume Bypass (or any other value)
. Wireless Switch Change = Denied
. Wi-Fi Catcher Change = Denied
. CPU XD Support = Enabled
. TPM Security = Off
. TPM Activation = Deactivate
. Computrace (R) = Deactivate
Performance:
. Multi Core Support = Enabled
. Dynamic Acceleration = Off (Can be set to On only with Penryn CPUs, keep Off with Merom CPUs or FSB and therefore CPU speed is reduced)
. SpeedStep Enable = Enabled
Power Management:
. Auto On Mode = Off
. Auto On Time = xxxxxx
. USB Wake Support = Off (USB wake support operates only when system is on mains and then causes Sleep/Instant Wake issues)
. Wake on LAN/WLAN = Off
Docking:
. Undocking Method = Hot Undock
. PCI Slot Monitoring = Enabled Silent
. Universal Connect = Enabled
POST Behavior:
. Adapter Warnings = Enabled
. Fn Key Emulation = Scroll Lock
. Fast Boot = Minimal
. Virtualization = Enabled or Disabled (only required to run virtual machines)
. Keypad (Embedded) = Fn Key Only
. Mouse/TouchPad = Touchpad-PS/2
. Numlock LED = On
. USB Emulation = Enabled
Wireless:
. Internal Bluetooth = Enabled
. Internal Wi-Fi = Enabled (keep to Disabled if you have an Intel card, they're not supported and need to be replaced)
. Internal Cellular = Enabled
. Wireless Switch = All
. Wi-Fi Catcher = Enabled
. LAN/Wi-Fi Auto Switch = Off

The above settings are compatible with sleep/wake mode of operation and use of Wireless on/off switch. BT + Wifi services resume on wake + wireless switch re-activation (Wifi may require manual network re-selection after the latter).

 'USB Wake Support' MUST be set to Off on nVidia models or laptop will not go to sleep mode but immediately wake. A fix via DSDT patching currently under investigation.