I don't have a full build idea, but maybe add a Rise MP6 (socket 7) to the list... or maybe a Transmeta Crusoe

S3 Savage2000 cards are also fairly rare.

Stuff like the alr revolution 6x6 comes to mind but for everything suggested thus far has been done even here on vogons already, could do a couple of exotic modern builds that would kinda make the list if I had the means to finish. Collected cards like the Quadro FX 4700 x2 ect including a pair of limited edition EVGA GTX 295 reds (only 500 were made and mostly exclusive to just the US) last year thanks to a lucky streak of decent prices during a period of low demand. I wish that I was able to get a 3DFX Voodoo 5 6000 back when they were only like $150 to $300 each.

kenrouholo wrote:

I don't have a full build idea, but maybe add a Rise MP6 (socket 7) to the list... or maybe a Transmeta Crusoe

S3 Savage2000 cards are also fairly rare.

MP6 is almost always available on ebay. Not sure if Crusoe has made into a socket-able version.
I had a Savage 2000 in the past when I was a poor student. Hard to make it work without BSOD.
Nx586, 5x86-150, K5-PR200 are quite rare.
V5-6000, Volari Duo are rare.

I've had almost everything from that list. I don't think they are that much rare... Maybe the Adlib Gold.

But I had (sold recently) a Mediatrix Audiotrix Pro with SFX daughtercard which I think I'ts hard to get.
I also have a CPU + mobo combo for Cyrix MediaGX MMX Enhanced which I think it's hard to come by too.

There are more rarer things than those in your list...

sprcorreia wrote:

There are more rarer things than those in your list...

No doubt. That's why I said I'm not very knowledgeable on rare retro components. I know the community here has lots of knowledge on this topic, I'm curious what you all come up with. Maybe even list a system build that would have multiple rare components in it.

apple 1 comes to mind as the rarest build

emosun wrote:

apple 1 comes to mind as the rarest build

You can do one for 150 bucks and the peripherals.

My RAREST build is an IBM EServer 325. It's prebuilt, but it has dual Xeons, hyperthreaded, and support for 12GB of PAE RAM. It has PCI-X, and an Ultra320 SCA-80 backplane, capable of 1.8TB in drives.

Forget Savage2000 - throw a PowerVR Neon250 in there 😀

lazibayer wrote:

Nx586, 5x86-150, K5-PR200 are quite rare.
V5-6000, Volari Duo are rare.

A pretty good start. Maybe match the later graphics cards with an engineering sample of a later CPU and add an Aureal SQ3500 for sound.

3dfx Rampage. Maybe some of the prototype Amiga stuff.

Next gen system?

gdjacobs wrote:

3dfx Rampage.

Perhaps. I imagine they're pretty useless in the state they'd be in, though. I mean, there's rarity and then there's the stuff that didn't even happen in any practical sense. 😀

Yeah, AAA systems.

https://www.youtube.com/watch?v=BaTjwo1ywcI
"I actually read on the net that these don't exist."
-- Dave Haynie, "The Deathbed Vigil"

Actually, pretty much everything Dave had on his desk would be great!

A pretty good start. Maybe match the later graphics cards with an engineering sample of a later CPU and add an Aureal SQ3500 for sound.

I have been counting the orphans of defunct manufacturers 😁 There are more: MII-433, S3 Chrome series, etc.
As for engineering samples... The other day we were talking about HD3870 AGP. It would be extremely exciting to find one of that.
I have an FireGL X2 with AGP Pro connector. It's not very rare but AFAIK it's the last make of AGP Pro video card for x86/64.

lazibayer wrote:

Nx586, 5x86-150, K5-PR200 are quite rare.
V5-6000, Volari Duo are rare.

^This

And stuff like prototype-only parts (think of the original Cyrix s370 CPU).

And in a way very rare concepts can be build using (for instant) ES CPUs.

Ampera wrote:

emosun wrote:

apple 1 comes to mind as the rarest build

You can do one for 150 bucks and the peripherals.

....a clone not a real one.

So maybe this as a fantasy retro PC:
K5-PR200
Hercules Stingray 64
Quantum Obsidian V1
Adlib Gold
Roland LAPC-I

Would that be relatively period correct to have all those in one PC?

Nvidia NV1
Videologic PowerVR Neon250
3DFX Voodoo5 6000 (working rev, like a 3700A or something)
Aureal SQ3500
Creative CT6200 (VLB)
Ad Lib Gold
Ad Lib (8-bit)
XGI Volari Ultra Duo
AMD K5-PR200
Cyrix 133/4X

Maybe we could "build" a 486-based system with the Creative 3D Blaster VLB. What other 486-era components could we use to complete the fantasy build? What about one of those early Pentium boards with VLB slots. 🤣