Dell Optiplex 790 - I've wasted $50 on fans for this POS now.

S

Sarra

Weaksauce
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Sep 2, 2017
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So, I got an Optiplex 790 a while back, and the hard drive fan promptly died.

I bought a new fan, my mistake, I got a 70mm instead of 80mm. It didn't fit, and it came from China, so no way to return it...

I bought a new fan, an 80mm 4 pin, and was just going to wire it in.

Hooked it up temporarily, and... Dell changed the wire colors.

So, it runs at 100% with black to black, yellow to yellow, red to red, and blue to blue, and gives a 'no fan error' still when I power it on. I really could give a crap less about the fan itself, but there is NO way to disable to fan warning on boot without the fan plugged in. I NEED this warning to be disabled, the custom bios does not give an option to remove it. I NEED this system to auto restart and log itself in when power fails and returns, or I may as well just toss the entire thing, along with another couple hundred $ in the trash.

Does anyone have an actual wire out for this fan? Googling turns up nothing useful.

PS: Never buying Dell ANYTHING again. Done with this crap.
 
Left is a standard 3 pin

Middle is *I think* the repinned one

Right is a stock dell fan
 

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There should be a dell part number on the existing fan or download the service manual and search for the actual dell part. It will probably cost around the same and will just plug in and work. I monkeyed around with some non-dell stuff on my finicky Precision 670 and the genuine dell parts finally took.
 
I think I figured it out.

So, I'll start by addressing SamirD... I found the Dell replacement fan, from Dell, for $30ish. The problem is that the Dell fan is a sleeve bearing, and I'd rather not waste money on a fan that has a limited lifespan.

As for the fan itself, the fan I bought is a Delta 80mm x 15mm fan, and it is a dual ball bearing fan (so it should last until just before the end of the universe). The problem is that the Delta fan pulls almost twice as much power compared to the stock fan, and I think it's pulling down the voltage on the fan header, and thus, the fan header is failing to detect the fan plugged in.

In the end, I decided that I'm going to part out the Dell, recycle the case and mainboard, and put the CPU, RAM, and hard drive into a new system. This way, I can get more than 1 hard drive, reasonable fan headers, and possibly even some extra functionality out of it. My second idea is to just resell the system at a loss, and buy a Ryzen 3 based replacement mini-server, and go all brand new components in it.
 
I think I'm going to build a mini atx Ryzen 3 system to replace the Dell. Picking out parts already... All I need is the board, CPU, RAM, and a case. I even would have use for the two fans I bought.
 
Sweet. And you should easily be able to get some cash for the dell carcass as there's still alot of people using them. (y)
 
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