Is the Dell Optiplex 780 mt with the Intel Core 2 Quad Q9550 still good in 2020?

If it works well for the things you use it for, then is still good.

I'm using an 8 year old machine, and I have another that is 20 years old and still works fine for most things.

If you want something newer, consider refurbs. They are much cheaper than brand new.

Adding to what donm4599x said - Current Optiplex's are very expensive; but back up a generation or 2, the refurbs are quite reasonable and more hardware can be added.

I was looking at a Dell Optiplex 9020 Tower with Intel Core i7 4770 for about $500 and a  Dell Optiplex 7020 Tower with Intel Core i5 4570 about $400 both are refurbished and I see others like these two that are 3 gen i5 or i7's around the same price range $300 to $600 depending in hardware installed. I have some memory that's designed for the 4th gen i series that should work( two kits of 8GB) it won't work on the one I have now won't post(light 2 and 4 light up and won't post). I guess memory for the newer i series won't work on the Core 2 Quads The only problem I ran into was only a minor one the drivers Windows 10 used for the onboard sound is buggy at times making me have to uninstall the drivers then reinstall after a restart. Only had that problem once or twice so far. This is the first Dell I ever owned I was always warned to stay away from them but I have to say I'm happy with this computer so far. It came with a 500GB hard driver with about 33.000 power on hours but was newer then the computer so it wasn't the stock drive. So unsure how many hours this computer got but it's working fine no real problems yet and also the temps seem very good the CPU runs around 33C to 38C idle and never hits over 60C when maxed out but I find maxing out the Q9550 isn't easy no matter what I'm doing the avg usage seems to be around 15% to 25% at the most even when I'm converting 1080HD videos off Youtube the cpu never goes past 40% used I was very shocked but what I am reading online about the Q9550 it's the top of the line of the Core 2 Quads with the Q9650 being only 3% faster then the Q9550. Coming from AMD computers before I got this Dell I was worried about temps I was always told Intel runs very hot but I guess Intel don't run that hot. I guess this computer has made me into a Dell fan I love how quite it runs I can't even hear it run I never had a computer that ran so quite and the two fans are running but only at idle speeds. I thought at first the fans weren't spinning.

Optiplex 780 Tech Guide 

Not sure where you're looking at refurbs, but it sounds like they're priced too high.  Ebay and Walmart.com are quite reasonable.  Amazon is a little over-priced.  I got my refurb 7010 I7-3770 for $143 (normally $189) Thanksgiving weekend through eBay from the Blind Center of Nevada.

so what are those questions, about old PC.?

most of what you hear are myths;  mobo goes bad. is one myth. (for sure the steel/alum in the case will not fail)

what does fail is the RTC coin cell this old, over 5-7 years the can and do often, expect this.

next is the HDD, no HDD with matching HOURs this old lasts.  run smart tests on it and learn if it is bad.(or going)" learn to look for  un-correctable bad sectors"

the next killer of all electronics is heat,  no way for me to know if your PC was run , in cold room or  hot or  even only  1hr per day . not me, but the smart test , shows hours on the HDD and is BIG clue that.

should I plan to buy another one just in case? (no)  easy, NO. why would you want 2 PCs with no cash. (for double trouble?) NO WAY. or dump this PC and get 3020mT, with Haswell chip sets)

It's like an  old CAR, with near 10 years of miles on it with say 200k miles,  and you ask how long  will it last.

there is no answer there either, ever. (unless I inspected it, sure)

now the endless, age old question about , RAM not being 16GB,  well the PCs chip set, dictates that.

the reason #1 is the HD graphic chip has no VRAM !< so the PC steals ram from the mAIN BANK OF DDR RAM.

CORE2  _  Intel® Q45 Express Chipset w/ICH10DO (series 4 south bridge rules) Q45 MMC runs the ram..

yes finding ram that works on Q45 is never easy in the year, 2020, due to rank, density rules are hard to match.

even the intel data sheet names this Q45 stolen memory, covers all that..  as do the books on this PC at dell

tell you all about stolen DDR... (2  or more causes, vram and Pci usage)

If you read the Haswell DS, it has new cure for  this but you do not have i3, i5, or i7 CPU.

hint2, some GPU cards used will lower this theft. (depends on BIOS and its versions)

page  116  DS

Graphics Base of Stolen Memory (GBSM): This register
contains bits 31:20 of the base address of stolen DRAM
memory. BIOS determines the base of graphics stolen
memory by subtracting the graphics stolen memory size
(PCI Device 0, offset 52h, bits 6:4) from TOLUD (PCI
Device 0, offset B0h, bits 15:4).
NOTE: This register is locked and becomes Read Only
when the D_LCK bit in the SMRAM register is set.

Adam, YOU Have so many rumors you hold.. (try to focus on 1 problem and we can solve them, for sure)

this post is on CORE2, not i3 up?

first off, staying a CPU runs hot, is not true. (actually the best ones and most fast CPU run the hottest)

sure older chips seem to ran hotter sure some lame PC laptops burn up, mostly from bad service, or poor heat sinks.

this topic is about ONE PC, not 4 or HP or any other PC nor about laptops, but lets go there.

Desktops many have huge CPU heat sinks, like my HP Z600 has, huge!. and will never overheat.

Workstations are more TOUGH. this way. in fact have 20 CPUs they can run there and are fully supported..

other makers, do not do that, some have 3 Heatsinks (to save a lousy buck) use tiny for Celeron junk and 60w for slow I3 and 100watt for i7, max..  

what matters only is YOUR PC and what CPU YOU have, and its Wattage rating (loss ) and the neat sink present. (and lint and dead '/weak fans sure)

welcome to newer computers that run fans slow, until needed, all modern PC do, and my ASUS Z270prime super slow super quite, PC. does. this.

you can not mix very old DDR between computers for sure core2, and i3 up.. 

the MMU is not the  same. at all , on both PCs, for sure mixing old , rank, density  DDR sticks fail , even the intel data  sheet on your CPU warns you this will fail. and why and what works and what does not.

that is why they sell CERTIFIED DDR RAM so you can avoid all that pain, and guess work.

if the sound chip fails gee turn it off and buy a card, end the  pain of old not supported w10 sound chips.. OK?

there are in fact vast things w10 does not support, (chip makers that died or do not support this line of chip  now)

endless.  If you want to talk heat  then please do, and there are solutions, every time on desktops.

ever seem this,,,,, ????  just one of 1000s of cases Ive seen. and cured.

if you were the engineer of this PC would you make the Heatsink 10 x larger to cover this guys mess????????

or this.

laptop ( one Laptop I have takes hours of labor to reach this place) all screws out and mobo pulled !

see my 3030 mt. see this photo I made,   see the difference,   I look here first. the right one is best,.

forget rumors,  learn to address exact issues, and solve those 1 by 1.  most have a solution. (ask)

ADAM,

DDR blues. right,?

well consider this,

how can some old DDR3 core2, PC MMC , work with new modern  2020, made, DDR chips DRAM.

that old old MMC is not magic it has fixed logic inside the MMC that can not even guess, what happened or exist in the year 2020.

this is called the G, moore effect,   for sure on DDR< for sure huge changes in chip (DRAM)_ Density.

that no CORE 2 chip set can use. Q45 

here is the Q45 page in the the intel data sheet from year 2008,(August) yea 12 years ago.

best means gen 4, best.

not the very serious limits here, it is Intels chip but Dell BIOS also has its own restrictions here.

the intel manual even stated, to not mix SKU.,  use a matched set, they tell you clear as day.

i3 even some mobo run DDR3,  (rare) not normal DDR4, that is useless in any DDR3 mobo or the reverse..

INTEL DUAL CORE I3 2100 CPU ASUS H61 Motherboard 8GB DDR3

and are problematic, for H61 chip sets.

The onboard sound card only seems to work after I reinstall the drivers but once I restart a second time the problem starts again I hear popping sounds even on the headphone jack but if I uninstall the drivers restart the computer Windows installs the drivers again it works again even if it's on for hours with no problems I had to going yesterday for 14 hours and it sounded great but after I turned it back on today the popping sounds are back. I was told this is a driver problem when I got this computer it had different drivers the ones that were meant for the onboard sound card but I have replaced the hard drive and I can't find these drivers that will work on Windows 10 nothing past Windows 7 is supported so how did someone find the right sound drivers before I got it? I went back to the video card sound card it sounds okay but the problem is my cheap TV I have to use the headphone jack and the sound it's perfect when hooked up to my stereo I liked the onboard sound better before these driver problems. Well I was told it's driver not hardware because if it was hardware the popping sounds wouldn't go away no matter what I do and reinstalling the drivers won't fix it. Can someone tell me how to get the drivers that will work on this onboard sound card? I know the input/mic jack works fine I started to record some of my records to MP4 and it works fine.

I never seen computers that dirty wow and I have been working on computers since Windows XP

I went on the Dell site for this computer and ran a search on the sound card and it seems it has a Soundmax Integrated Digital High Definition Audio sound card I was able to find a another Dell site that had newer drivers with Windows 10 support listed for it and I have downloaded and installed them I did a manual install of the drivers through Windows and so far it worked Windows is detecting the sound card as "Soundmax Integrated Digital High Definition Audio" I will know for sure after I restart it a few more times but it seems okay after 2 restarts.

https://www.dell.com/support/home/ca/en/19/drivers/driversdetails?driverid=8r56m.%C2%A0

Thanks for accepting a couple of my posts as solutions.

Here's a couple photos of my 755 you might like.  The appearance of wires I wasn't as concerned about compared to functionality and besides, I wasn't inserting a window into the side panel.

Pictures are not showing

They'll show once approved by a moderator.  Also, in Android, one has to be signed out in order to see photos.  If I'm already signed in, I sign out and use the back arrow.

if you have  a PCI-e card SOUND/Audio?

tell what it is ., nobody can guess cards, ever, only told works.

or all answers will be wrong, open case look at all PCI lots and read the names on the cards with green 3.5mm sound line out jacks, tell this first.  we can not see inside your case ever. unless you post a photo ,thanks.