"The 790, along with other models utilizing diagnostic lights, does normally flash them a few times at startup."
lol. Right, I know, I'm just not sure if there's a pattern they blink in. I assume there is, but since it was cycling over & over I shared that pattern in case it was helpful to anyone, I assume it is the same flash pattern it just freezes at the CPU check, but I can't say as the normal pattern goes so quickly & I don't pay attention to it

The 790, along with other models utilizing diagnostic lights, does normally flash them a few times at startup.

I'm pretty sure this was the thread whereas I forgot mention sooner, and you might know already anyway - Chipset might support one thing, but not the Dell MB.  Sell more PC's that way.

"the 3010MT that uses a standard 4-Pin Fan Header for the CPU

& standard 3-Pins Fan Header for the 2 case fan headers."

While that might be true the 790 (9DVNN) fan and 3020 (89R8J)

are lumped in here as well and they do not have standard fan connections. 3020 has proprietary power supply connections.

3020. 7020. 9020

Dell OEM 365w PSU =
7VK45 365w, Huntkey
T1M43 365w, Delta

https://raphtec.wordpress.com/projects/dell-poweredge-t20-atx-power-supply-adapter/

https://www.moddiy.com/products/Dell-Inspiron-3650-PSU-Main-Power-24-Pin-to-8-Pin-Adapter-Cable-30cm.html

Its not helpful to leave out that kind of detail.

users have also found on some dell systems that some fans require 2500 rpm max or it will post an error.

The other reason why a new motherboard is probably not a good idea is because you have to buy a new Windows License, Office License, etc.

Dell Fan Wires

Screengrabs go in this order - 3020, 7020, & 9020 showing MT models:

Not a problem that 365w PSU's work in these models, but they aren't standard.  What models do the 365w PSU's come from?  I imagine one answer might be Precision.

Hi @Dr.Mxyztplk ,

"...if you are moving a board INTO a 790 case, as, at least in the Desktop model, the standoffs are permanent parts of the case.

So the 790 case would NOT be compatible with the Optiplex 3010"

So if it's the 790 DT you were working with, is the 3010 also a DT?  I might've missed it in this long thread.

I'm sure you noticed too that the 790 has rear PS/2 ports and not for the 3010.

An important update I believe. So I just discovered moving the 790 to a different case, that there's an issue with the standoffs. For some reason the 790 case has weird standoffs, they are slightly taller than the standard standoffs. When moving a board from the 790 into another case it will sit & Match Up to the Standard MicroATX standoff positions, but the IO Shield won't line up & your ports will be slightly lower than their holes. Worse the riser cards (PCIe) won't fully seat. This can be solved with the 790 Board in another system by putting a small washer to prevent the standoffs from screwing in fully, I'd recommend putting them between the case & standoff rather than between the standoff & the board to prevent them from making contact with the traces. I made my own washers using cut up target gift cards, 3 pieces thick (given mostly to demonstrate the slight height adjustment needed), which gives a close enough rise to let the cards seat properly & the IO ports to line up enough to be usable while still having the standoffs stew in securely. You could also buy taller standoffs from a hardware store like Ace, but I do not know the exact size you'd need. As this system is one that is in my own home not made for someone else I am fine leaving the plastic cards as spacers but it's not a solution I'd recommend personally.

This creates a much bigger problem if you are moving a board INTO a 790 case, as, at least in the Desktop model, the standoffs are permanent parts of the case.

So the 790 case would NOT be compatible with the Optiplex 3010

There are no standoffs.

Several models IO shield is also not removable its part of the case.

And As far as the USB and 20 pin front panel connectors these are not standard.

20 pin front panel

No Idea why you say these are standard.

"So if it's the 790 DT you were working with, is the 3010 also a DT?  I might've missed it in this long thread."
The 790 is a Desktop while the 3010 is a MT Tower. But according to Dell support they use the same motherboard until you get to SFF & USFF, which each use a different board. If anything the 790 has a larger board than the 3010 so I easily believed that, but there is, of course, like the 3010's diagnostic lights, possibilities that there are exceptions. But all I know for sure is that the 790D has non-standard standoffs, while the 3010MT has standard sized ones (though they are also built-in).
 
"I'm sure you noticed too that the 790 has rear PS/2 ports and not for the 3010."
I am aware, but those are within the IO Shield Panel. Moving the board you must also pop out its IO Shield & move it with. That's a common misconception people have. Almost all computers use the standard IO Shield. It's a removable piece that you pop out of one computer & into another, that way all your Onboard Ports can be whatever & still be compatible. The problem with the 790 is that since the standoffs are taller where the holes in the 790's IO Shield line up is based on a different starting point. I put both the 3010 & the 790 in standard ATX & MicroATX cases respectively. As everything in the 3010 aligns to the ATX standards it's case too is standard MicroATX. Currently the 3010 case has a MicroATX board in it for storage purposes until those parts get used, the case has an ASRock AM1B-ITX board in it, no physical dimension issues & the IO Shield lines up fine. Looking down the 790 lines up fine too, but the IO & card slots are just slightly off, enough that you have to adjust for it to make it work. Dell officially doesn't say their boards are standard, they call them all "proprietary" but since everyone makes things to the standard it'd be more expensive for the pieces if they wanted them truly proprietary. Since the IO Shields are made unique for each board & the case is theirs they can make little adjustments like that, since it's a custom fab, & the fans use a generic 5-Pin connecter used in others things so they just buy that piece instead of the other, standard one & the price difference is negligible. But it makes it harder on their users replacing a part that will eventually wear out so most will buy replacements from them or get another system because it's easier. But all in all though Dell does not make things necessarily easy for their users, they do a much better job than many others. The one abbreviated the same as that famous English wizard is much worse & I sometimes feel they spend extra time & money for the sole purpose of making things hard for their users. Like making their unlabeled RAM & SATA ports have to be used in a specific order or the system won't POST. The system is designed to not care, so they had to add that. I've also run into the wizard making custom motherboards that have non-standard standoff locations, & even once I ran into one that had the spacing to the card slots off by half a card, so you had to cut off the slot dividers to use a PCIe card at all & drill an anchor screw hole if you moved cases or boards. Just so users are more likely to send things in to be fixed or upgraded instead of doing it themselves.

"There are no standoffs."
They are, they just are permanently attached ones... as I've already said. Stop trying to make problems

"Several models IO shield is also not removable its part of the case."
We are talking about specific models. Whether or not other dell models do or not is not relevant here. But EVERY Optiplex models that I've seen has a removable IO Shield. & every Dell except some SFF ones. I currently have in my workshop:

• Optiplex 3010 MT - Removable IO Shield
• Optiplex 790 DT - Removable IO Shield
• Inspiron 660 I think SFF - Removable IO Shield
• Inspiron 580 MT - Removable IO Shield

I've worked on other Dells & other Dell Optiplexes, & none of them had non-removable ones. Now this does not mean that there aren't ones that do, but THIS discussion is about the 3010 primarily & the 3020 & 790 as well. The 3020 MT & DT have removable ones, though the SFF looks to possibly not, but the pictures are inconclusive, I'd have to see one in front of me to say for certain. But we've already established that the 3020 has a different socket & is therefore not a compatible board. 

"And As far as the USB and 20 pin front panel connectors these are not standard."
It has already been addressed that the 3010 has a STANDARD USB2 Header as well as a STANDARD HDAUDIO Header. We also established that the 790 has the diagnostic lights, USB2 Headers & Audio Header are in a single off-sized connector. We also established that these are not required & that they will likely be transferable from MT to MT & from Desktop to Desktop cases. The 790 DOES have a single standard USB2 Header, which could be used to provide USB to a different Header from the 3010. The only proprietary connectors on the 3010 are for the diagnostic lights which, we already stated, should transfer & are not required & for the power button which both systems use the same proprietary connector. 

"users have also found on some dell systems that some fans require 2500 rpm max or it will post an error."
You provide no sources so that information is neither valid nor relevant to this thread since neither the 3010 nor the 790 have that problem. And since that sounds quite ridiculous, evidence is required before that statement can even be acknowledged, let alone considered relevant here.

"The other reason why a new motherboard is probably not a good idea is because you have to buy a new Windows License, Office License, etc."
100% Untrue. According to Microsoft changing hardware, including a motherboard, does NOT require a new License. In fact Microsoft has a whole page about how to reactivate your license if it is disconnected after a significant hardware change like a motherboard. Motherboards are specifically listed.
Reactivating Windows 10 after a hardware change 

"While that might be true the 790 (9DVNN) fan and 3020 (89R8J) are lumped in here as well and they do not have standard fan connections. 3020 has proprietary power supply connections."
The 3020 has been dismissed multiple times as it is not a compatible board. The 790s fan connectors HAS been addressed as well as a $1 piece available on eBay to adapt it as well as the ability to move the fans with the board if needed. But even if the 3020 WAS being used the proprietary PSU, if it indeed has one, which I could not care to check as it is irrelevant here, that PSU could be moved with the board as well, though if someone was replacing a 3010 with a 3020 then there would be little point in moving the board as the cases are THE SAME aside from things like the 3020 having front USB3 headers instead of USB2. Like shown in your image.

All,

Due to power outages here in central Texas, I am only on periodically.

Please review your post. Edit/remove any personal attacks of other users. Calling another user a troll, accusing them of providing false information, etc. are all attacks. You all can have differing opinions without being mean to each other. We can only speak to the validated OEM PSU and video cards.

Optiplex models have been around 27 years with the first ones 1993.

" But EVERY Optiplex models that I've seen has a removable IO Shield"

Therefore this is not correct.

Dell Optiplex from 2005 to 2009 used the Micro BTX cases . The first model to sport the new BTX case was GX280 which changed to GX620 in 2006. Optiplex 320 330 360 745 755 760 780 980 are based on the built into the case I/O shield.   Not sure how you can say metal bumps in case are standoffs.

Newer models like 390 790 990 do have I/O shield.

Varies for 3010 3020 7010 7020 9010 9020 because there are Micro and AIO models.  So the blanket statement about standoffs and I/O connections etc is also incorrect. Once you get to 3020 7020 9020 the power supplies become VERY proprietary.

There is even someone who made his own adapter instead of using MODDIY.

https://raphtec.wordpress.com/projects/dell-poweredge-t20-atx-power-supply-adapter/

THERE ARE ZERO STANDOFFS HERE

Other than REALLY OLD dell models with 8088 cpu I know of NO DELL MODELS That use standoffs.

EPS which it is not, &. EPS12v references the 24 PIN connector vs 20.As well as the combined power max for 3.3v/5v rails and the UL 94V safety rating.

that it is 80 Plus certified, which it is not,

saying that it is a PFC unit, which it is not.  It says PFC (ACTIVE POWER FACTOR CORRECTION) power supply in the spec and has for more than 10 years for ALL dell models.

709MT is 80 plus GOLD PFC power supply for 790 as well as 3010.

The EPA Energy STAR versions are REQUIRED to be at least 80 percent efficient and they are ALL Active Power Correction Factor (PFC)

@DELL-Chris M  can verify this.

March 15, 1992. 28 years ago. Version 5 goes went into dell as early as 2009.

https://www.dell.com/downloads/global/products/optix/EnergStar5.0_SpecSheet.pdf

PFC 80 Percent EPA

"Optiplex models have been around 27 years with the first ones 1993.
'But EVERY Optiplex models that I've seen has a removable IO Shield'
Therefore this is not correct."
You are intentionally taking things out of context, I specified before that that I don't know about all other Dell models, but that every one I've seen has a removable one. "Now this does not mean that there aren't ones that do, but THIS discussion is about the 3010 primarily & the 3020 & 790 as well." Now I've probably seen old Dells that don't, but in a conversation about specific ATX boards referring to an older incompatible technology is no different than referring to a car part.

"Dell Optiplex from 2005 to 2009 used the Micro BTX cases"
This is completely irrelevant to this discussion. BTX boards are not compatible & in no way relevant here. But I'll repeat what I said in a different thread that you are trying to bring up again, The failed BTX Standard was canceled by Intel in 2006. Any further posts about BTX will be passed over as they are not relevant here.
Linus Explains Power Supplies (He mentions BTX only as a "No-longer-relevant" specifically "Defunct" comment)

"Not sure how you can say metal bumps in case are standoffs."
So the definition of "Standoff" apparently is "A standoff is a threaded separator of defined length used to raise one part in an assembly above another." But I specified that they were "permanent" ones. So I suppose "Technically" they are not "Standoffs" because they are not threaded. But they server the purpose OF standoffs, are used WHERE standoffs normally are, use the standoff holes, & I was comfortable with the fact that everyone who knew how to take a motherboard out, what this discussion is about, would reasonably understand my meaning. They literally STAND the motherboard OFF of the frame of the case. You obviously don't know what to call them either, so you called them the "Metal bumps in case". 

"Once you get to 3020 7020 9020 the power supplies become VERY proprietary."
Not relevant to the discussion stop trying to sidetrack

"The only difference between the 790 DT & MT's MB is the DT has one less SATA port."
Interesting, according to the documentation I looked at awhile ago the motherboards were listed as the same model number. I'll have to find that stuff, maybe I misread something.

" 'EPS which it is not', &. EPS12v references the 24 PIN connector vs 20 . As well as the combined power max for 3.3v/5v rails and the UL 94V safety rating."
At least I now understand where the confusion is. EPS has nothing to do with the large 20 or 24-pin Motherboard power. Rather it refers to the 2nd power to the motherboard for the CPU from the PSU. EPS are the 8-Pin connectors that connect next to the CPU. It's a subset of the ATX standard. Linus mentions this in the video I posted above.
This is from the A+ (Computer Repair Certification) Manual
Some motherboards use power supplies that feature several additional connectors to supply added power, as follows:

• The four-wire square ATX12V connector provides additional 12V power to the motherboard; this connector is sometimes referred to as a “P4” or “Pentium 4” connector.
• Many recent high-end power supplies use the eight-wire EPS12V connector (see Figure 4-6) instead of the ATX12V power connector. Often, the EPS12V lead is split into two four-wire square connectors to be compatible with motherboards that use either ATX12V or EPS12V power leads.
• Some older motherboards use a six-wire AUX connector to provide additional power.
  
• [Figure 4-6]
• https://www.pearsonitcertification.com/articles/article.aspx?p=1945640
• 

" It says PFC (ACTIVE POWER FACTOR CORRECTION) power supply in the spec and has for more than 10 years for ALL dell models.
709MT is 80 plus GOLD PFC power supply for 790 as well as 3010 .
The EPA Energy STAR versions are REQUIRED to be at least 80 percent efficient and they are ALL Active Power Correction Factor (PFC)"
So the Optiplex 3010MT has a power supply with model number H265AM-00
It's not in any specs that I can find for it being Active PFC. It has no Energy Star label on either the Tower or the PSU, neither does the 790DT. While it is general practice for PSUs to have voltage selectors if they are not PFC, that has often not been the case for prebuilt units. So I decided to open up the PSU since it happens to be out & easily accessible at the moment. I noticed that it does seem to have a circuit board in it which could, not my area of expertise so I could easily be wrong, be an active PFC chip. So despite the fact that the specs do not list it as PFC, nothing on the PSU indicates it as PFC, I believe it most like IS an active PFC unit. So I was most likely wrong about that. But still, either way, it being or not is beneficial to protection against surges, it is not required or even known by the system.
3010 PSU (No 80 Plus Sticker)Inside H265AMBIST (Self Test) PCBPossible PFC Circuit
As far as the 80 Plus Rating I have no idea what it's efficiency rating is. It has no bearing on this discussion, but even though almost all PSUs are 80% it hasn't been certified for 80% efficiency at all required loads by the 80 Plus certification. It is therefore an Unknown Efficiency unit. Not an 80 Plus unit. The image you posted was an H240ES-00 Unit, which is not only NOT the one in the 3010, it is not even the correct form factor as it's for the SFF model. It is the possibly SFX form factor, the same in my 790. My 790 has a model H250AD-00, which also does not have an energy star or 80 Plus logo on it. I assume the "ES" in the model number is for "Energy Star" which these do not have. 

These comments are not about matters of opinions, they are about facts. 

All,

Reminders were posted about negative tone, attacks, etc. in your responses.

Edits commencing. We are not going to delete any replies. We are not saying who is correct or incorrect. All we care about is that personal attacks must cease. You can state a contrary position without attacking each other.