9020SFF POST/SSD issue?

Besides all that, does your 9020 have at least 8GB RAM?  At least 8GB works better and faster with Win10.  It'll also boot faster than 4GB.

Check BIOS Boot Sequence and make sure it's either checked on the SSD or Windows Boot Manager.  I'm guessing you got the 9020 as a refurb?  Then it may have been on a bootable network.  My 7010 had something like IPV4 and IPV6.  For some reason, that didn't become a problem until later.  They got unchecked or deleted.

Can also try a different SSD/HDD in case the one you have is failing.  Running Diagnostics from the Boot & Diagnostic Menu (F12) is an option.  There's also downloads that can check the health of your SSD.  30 sec. to boot from an SSD sounds a little slow.

I'm sure very familiar - First, if not done in the last 5 years, replace the size 2032 CMOS battery.  Bad batteries cause boot problems.

It's possible rear fan isn't providing proper feedback to the MB.  May need replacing or hit F1 to continue after booting.  But let's get to the other troubleshooting stuff first and see if we can cut out that overly long boot time.

This post shows my 9020 in all of its glory. Everything is "maxed out" on it.  I guess I'll try replacing the good ol 2032 and see what happens. I got this PC back in June 2022 off of eBay and I don't remember changing the battery... I swear, I thought I did.  I'll also get a random "rear fan failure" error message, but when I open it up, I can clearly see that all the fans are running smoothly. 

My 9020 sff also had a slow post after new memory stick install, but only at the very first time of power on. Power button stays solid white. No video at all, no Dell logo. Monitor has amber light. When post is done after 1 minute or so, monitor has green + video signal.  I think replacing cmos battery is a good idea in case the cmos settings has degraded over time after initial eBay purchase.
I think I also got a transient rear fan error, which did not reoccur.

A couple of ideas to check SSD health:

• CrystalDiskInfo free download 
• How to Check SSD Health in Windows 10 & 11 Tom's Hardware 

Alright, I replaced the battery with a brand spanking new Durasmell 2032. Did a CMOS clear and RTC clear as well. I thought I nearly bricked it, but was able to recover and re-set BIOS parameters. Now it only sits for about 10-15 seconds before booting, so it looks like it partially helped. Did a Restart and a full Shutdown/power up sequence, and now it's consistent. So I'm thinking it might be the SSD. I'll order one this week and see what happens. 

Ran the CrystalDisk utility. Looks like the drives are fine.(100% on both)  So, no point in getting a new drive. I suppose I could just live with it for now... it is an almost 8 year old PC.

Glad the SSD is good.

Up to you if you want to check on the stuff in BIOS mentioned in my first reply.

With redxps' RAM mention, I'd be tempted to check 1 stick at a time and see how it does.  If PC boots faster with all individual sticks, I'd reinstall the sticks until PC slows down again.  The caveat is you might have to boot each stick twice since first boot might be slower with hardware change; or it may just do that on the first stick until more RAM is reinstalled.

just a side comment based on my recent experience. 9020 with i7-4790 used to be a very good model and still good now, but I find the 5050 has a more classy front bezel and simple elegant internal hdd caddy design.  The price of that model w i5-7600, 16 gb 256 gb ssd can be got on eBay for $100 including shipping, so it does not make much sense nowadays to buy 9020 at a comparable price.

pro: new model, newer cpu (still not Win 11), faster memory

con: more expensive ddr4, no vga onboard video, all DP now 

Last pgh. in above post was added to.

@bradthetechnut I did check BIOS settings while reconfiguring everything - it looks like it was some sort of media storage PC in its past life; I saw the name "CDServer." However, I did not see any indication that it was booted from the NIC.  Regarding the memory - one thing I might try doing is put in a different memory kit - I'll be purchasing a new kit for another 9020 (MT) that I'm working on, so maybe I could put that in the SFF and see if there's any difference.

@redxps630  I do like the look of the next gen series (30/50/7040 series onwards) There was a couple of 3040 SFFs in the dumpster when I got my 3020s, and I didn't think to grab them (d'oh!) Most of the PCs I have I got for free; my 9020 SFF is probably the only exception.  (I'm embarrassed to say that I paid way too much for this PC after all the upgrades just to make it a novelty gamer PC) I'm still waiting on more dumpster PCs... at work we mainly use 70/9020 MTs for testing, although I've seen 70/9010s as well, and even a 990 MT. The SFFs we use are mainly just for data entry, and those are mostly 3020 SFFs (though I'll see the older 790 and 390 as well.) The oldest PC still in service is an old GX260 MT.

No doubt that the 5050 is a good machine.  But I can do more with a 7010 (or 9020) than I can with a 5050 due to its hardware limitations.  If it wasn't for the hardware limitations on some newer Optiplex's, I'd more easily buy a newer tower.  By the way, those are good deals on 5050's on eBay.