Has anyone tried to upgrade Dell Optiplex 990 from Windows 7 Pro to Windows 10? I'm having problems upgrading and could use some advice.
Best advice is not to upgrade. Windows 10 can be installed on almost any computer but it doesn't run well on all of them especially older models with windows 7. It can make computers fail. Since you never upgraded to windows 8.1 on that computer, you shouldn't install windows 10 now. Wait until you replace your computer to get windows 10. Check the Dell list for models that can be updated. The 990 is not on it. Heed the warning.
I upgraded my 990 MT i7-2600 from Windows 7 Pro to Windows 10 Pro in August. The Win10 install was flawless. I immediately migrated the OS to an SSD. My wife uses this machine for desktop publishing. She loves it
My 9020 MT i7-4790k runs Windows 10 Pro installed on an ssd in late September. Again, the installation was error-free. Windows 7 Pro now seems "primitive". Windows 10 has a richer interface and it just feels smooth. I enjoy the multiple virtual desktops -- I keep my diagnostic/measurement tools separate from general applications.
Optiplex 9020 MT Intel Core i7-4790K 4.0 GHz 20 GB DDR3-1600 Samsung 850 Pro 256 GB SSD WD 500 GB HDD
Optiplex 990 MT Intel Core i7-2600 3.4 GHz 16 GB DDR3-1333 Samsung 850 Pro 128 GB SSD ST 500 GB HDD
ASUS G50vt RoG laptop Intel dual-core P8400 2.66 GHz
Yes ensure you have the latest (UEFI) BIOS:
Also see if you have the options to arm UEFI and Secureboot.
Then await proper Windows 10 deployment i.e. Windows 10 TH2, which is out on the Insider Slow track now and should be out on the maintrack any time soon. I will update this guide as soon as I get my hands on the TH2 .iso:
I've found Windows 10 installed painlessly as upgrades over Windows 7 Pro (64x) on all but one of our Optiplex 990's. Admittedly, I've done them all in July of 2016. My one problem-child didn't get proper drivers so the graphics are a bit old-school. Not sure where Mary G is getting her "information."