I have another BX6r2, but it should probably get a recap. And if I ever go there, I'll probably want to explore modding it (potentially better power MOSFETs and a few other things I would change, given unlimited time to experiment). I just don't have the space to have a lot of backup parts.

Honestly, the most likely thing to blow up is this Antec power supply from 2004 (all original). I can almost guarantee I don't want to look inside of it, given that it is from the middle of the plague.

Not just motherboards, but also CPU's and graphics cards. one or two spares for each build. They are getting hard to find so better to be ready...

I don't explicitly have backups of identical boards for a specific build, but I have so many motherboards overall that there's plenty of overlap in what they're good for.
If I can think of anything unique about a particular board, or I just think I might use it in a build, then I end up wanting to keep it. That can get out of hand.
Especially when I start thinking "I want to benchmark every hardware variation of XYZ someday".
I need to sell some boards off and shrink the collection, but I loathe selling motherboards because of all the 100 ways the buyer might have a problem with them.

Some boards i do have the same as spare, but not intentionally. They came in boxes of random stuff mostly.
There how i got 3 Tyan dual slot 1 boards and 3 P4C800-3 :p
And with my Deskpro XE came a spare board, but I wouldn't have bought it separately.

I have a lot of spareparts for some of my systems as well as complete duplicate systems.
For many OEM builds like Compaq, HP, IBM, SNI or Dell it is easier to find and cheaper to buy a complete system, than only a mobo or a proprietary PSU.
In contrary I do not have any 1:1 replacements for any the systems I build mysef from generic parts.

Some of them I have. Some of them are so rare it would be impossible to have a spare for it.

My build is pretty vanilla, but I have backups of everything. My CPU/MB/RAM combo I believe I have 3 complete systems.

875PBZ/3.2 Northwood’s

It’s not the hardware that is lusted over in most threads but for under a 100 bucks a “system” I couldn’t pass it up. VGA not included.

I don't have spares if that means exact same motherboard to replace in case old one fails but I have enough parts that I can build another system to replace the any ones I have that can do same things.

Horun wrote on 2023-12-19, 05:06:

I am wondering how many members have a duplicate motherboard for some of their builds. For a few of my fav old builds I obtaine […]
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I am wondering how many members have a duplicate motherboard for some of their builds.
For a few of my fav old builds I obtained a spare working motherboard of same make and model, just wondering if any one else has done this.
Example of my dupe boards in case one dies: FIC 503+, Asus P2B-F, Gigabyte GA-8iPE1000-G, Asrock Penryn1600.
Am not so worried about 286, 386, 486 as near any in storage will work as a replacement....
Just curious if I am one of the few that OCD told me to get another exact board 😀

No backup motherboard, but I do have similar complete backup builds.

I used to have 5+ retro machines built but over the years I've fine tuned that down to 1 socket 7 machine that I love, so yes I have duplicate motherboards for that (and all of the other bits). I've spent years perfecting this build and if something goes wrong I want to be able to replace it and get exactly the same experience. It's not a fancy motherboard but it's the one for me, right down to a specific revision 😁

I've got more builds existing more "in potentia" than actually together and running, but in theory I have backup exact match boards for 5 of those, then for another dozen "near enough", though this situation is existing due to a lack of paring down and selectivity rather than trying to get many of the same thing.

I totally see the point though of deliberately holding a backup board for one or two perfect systems particularly if that's all you have room for. Not so much at the moment for my case where I have a lot of "more or less the same thing" until I get the built and tuned builds more firmly entrenched as keepers then may retain parts to support them. So far touch wood though, I'm mostly going the other way, acquired parts assumed dead and get them working..... meaning in the main I've resurrected more than I've killed.

Spares all the way!
Back in the day (18 years ago now! how time flies...) I started buying up motherboards in particular, of select models I had had good experiences with.
As I knew already then how hard old mobos are to find later on, if you want a specific one. And for some reason, my chosen slot 1 mobo worked nonstop (daily) for 13 years before the large 4 Vcore regulator caps finally caved, after having the Celeron on constanst high voltage overclock 😊.
Good thing I had 11 spares* of that model by then, L O L! The busted one is still here though, waiting (in vain?) for a future recap.
(*:some bought on ebay for £1/$1 + postage.... oh, those were the days, when they where considered mere junk)

And, when buying new mobos, I always buy at least 2x of the exact same, sometimes 3x, if that model has a special and long time retro related purpose.
The other parts, apart from graphics cards, are normally much easier to score years later.
Most recent was buying 3 copies of a certain AMD X470 motherboard, for my windows 7 build.