apple mac pro a1186 it chimes on start-up but no display

Seeing any error symbol say the graphics card (in addition to the rest of your Mac Pro) is working and that card supports MacOS boot screens!

The question mark is saying, "I could not find no boot drive where you told me to look." NB>> sometimes only the "where you told me" part is what got damaged.

if you hold the Option key at startup, your Mac should draw a gray background on the display, then over the next several minutes will add an icon for each potentially-bootable Volume it discovers by brute force searching for drives.

does it stay just gray screen after five minutes? (the WAIT cursor usually converts to the standard pointer after it has looked everywhere once.

Did you put your USB-stick Installer in the USB slot? if not recognized, the stick may be defective or not built properly to be stand-alone BOOTABLE.

<< Did I through my [windows 10] laptop >>

Oh. That can get you the Installer, but it is unlikely to make a good BOOTABLE installer DRIVE that works reliably.

I will post my ordered list of ways to get an older Mac going in the next post.

the solid Apple is not in the Mac's ROM at startup. Seeing the solid apple appear says your graphics card supports boot screens, AND the first Blob of software was loaded successfully off the boot drive (that drive appears to be bootable).

at that point the graphics card transitions to its loaded Driver software. what you now appear to have is a row of scrambled dat across the center of the dimply, suggesting that your graphics card was NORT abo=le to make the leap to system Driver.

Safe mode does not use the System driver -- it stays in Boot Screen mode.

do this>> Restart in Safe Mode (by holding Shift as early as possible) and see if you get farther.

The initial "chime" sound is generated in software when your Mac passes the Power-On Self Test. If the chime occurs and/or startup continues, your Mac is working. The screen should light up and draw a blank gray screen. Then on to the Disk Drive.

Accessing the Boot drive:

The solid Apple is not in the Mac's ROM at Cold start. The Apple logo can only appear when it is fetched in the first "blob" of software loaded from a 'magic' place on the boot drive, or re-run after a Restart. Then a whole lot of stuff is initialized, and the progress Bar moves part way across. After a cold start, seeing the solid Apple appear says your drive was able to produce the software that contains the Apple logo.

If a prohibitory sign appears at this point, it indicates some fundamental part of MacOS is damaged or wrong version.

Mounting the Boot drive:

The next step requires a lot of files by name, so the File System is initialized, and the Boot Drive is Mounted. If the drive directory is damaged, the drive can not be Mounted, so your Mac begins one pass of Disk Utility Repair. This will take an additional about five minutes. During this process, the progress bar may be extended, and will grow by an additional amount not seen on a routine startup.

at the end of that process (which should not take more than about five minutes), it will attempt to Mount the drive again:

-- if the drive Mounts, boot-up continues.

-- if the drive cannot be Mounted, your Mac can do nothing more, so it powers off.

what shows on the display?

-- nothing at all. display card has died

-- flashing question mark. can't find no bootable drive

--- Prohibitory sign (circle with slash) your drive seemed bootable, but very early in the process, a major component was not found, wrong version, or defective

does it still have the colorful band of snow you posted before?

You do not need an internet connection until you have booted up the installer, it has placed the install image onto your new boot drive (which can take half an hour) and it is ready to activate your NEW Installed copy of MacOS. At that point, it is smart enough to complain specifically about 'no internet' with a clear error message saying it wants an internet connection.

Be sure to apply all available updates to 10.9.5 using Software update.

This will provide a newer version of Safari, Safari 9, that CAN get access to the internet. once you have ANY version of MacOS installed and using, using the full power of macOS to get later versions will be far easier.

As I Sid before, Wi-Fi is not a requirement. but a way to connect to the Internet Is required.

You should be able to plug in an Ethernet cable and get an Ethernet connection. If not, readers can help you get it working. (but it may be better to start a NEW discussion, and gib=ve it a Title that will attract Readers with the expertise you need for Ethernet.)

<did not chime>

The initial "chime" sound is generated in software when your Mac passes the Power-On Self Test. If the chime occurs and/or startup continues, your Mac is working. The screen should light up and draw a blank gray screen.  Then on to the Disk Drive.

if it did Not chime, did the fans spin up?

if the fans spin up, is the power-on indicator blinking a code?

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