owbp

MyHack will work with almost any .dmg you throw at it IIRC. Missing Bt Ctrl is caused by video card, or VT-d in bios. But I had it also when forgot to copy FakeSMC to installer. Anyways you should skip distros and go Vanilla as much as possible.

Ok, i'll paste this guide for you so you can decide what OS X you want to install http://www.insanelymac.com/forum/topic/280756-guide-the-all-in-one-guide-to-vanilla-os-x-including-chameleon-dsdt-for-beginners-updated-for-yosemite/ This is with Chameleon boot loader, I'm still trying to figure out how to make Yosemite Clover, but ML and Mavericks work great with Clover too, same kext as with Chameleon. You can download Bootpack from this forum for Optiplex 755 with working kexts, smbios and boot.chameleon.plist, but since i never found any use for some kexts from bootpack, ill attach my combo of kexts for Mavericks and Yosemite. ML needs only FakeSMC (AppeIntelE1000e and VoodooHDA at post install for LAN and sound). You'll need to patch AppleRTC for CMOS reset fix. And maybe add efi strings for GT210, but it should work OOB. In BIOS load default settings and then enable Intel Speedstep, but only for Yosemite you'll have to put SATA Controller on ATA or Legacy. For ML and Mavericks it should stay on AHCI. Feel free to ask if there is anything confusing you. P.S. This topic should really be moved to appropriate sub forum. Mavericks 755 Kexts.zip Yosemite 755 Kexts.zip

All Core2Duo CPUs work well, so no need to worry about that. Optiplex 755 works great with Mountain Lion, Mavericks and Yosemite so what OSX would you like to install on it? The only thing is, Q35 Express Graphics isn't supported so you'll have to buy some cheap Geforce (GT210, GT610, or older GT220 and so on...) to get QE/CI graphics acceleration. Regarding your Dell D630, have you tried this guide? https://osxlatitude.com/index.php?/topic/1643-dell-d630-mountain-lion-install-guide/