Do you have two boards with CPUs on them? The chips with the heatsinks are likely the actual CPUs, the chips next to them are , from what I can see in the pictures 82495 cache controllers and the little chips under the heatsinks are the l2 cache chips. I ask if you have two boards because if not, it's only a dual CPU. Still cool and I hope you get it working.

Shoot, you're right. I never paid much attention to the big number, only DX-50 and it having the same pin count and package as a 486. Edited post to mark as such.

This is a beast! Absolutely tremendous system you have there.

I remember passing by and seeing it but being all the way over here in the UK I was powerless (no pun!) to do anything about it.

You've wrote this thread at a really good time, I'm right into dual 486 CPU servers at the moment and appreciate you taking the time to post pictures along with the write-up.

That riser board is insane! Also, the soundFX from the PSU in that clip sounds a bit creepy, cry for help maybe?

So is the system after all a dual or quad system?

If/when it's up and running, will you be willing to take benchmarks of the systems performance?

Again, fantastic system!

Dual 486 it is. I'd be glad to do benchmarks once I get it up and going, just give me a list of what you'd like and I can try to get it done.

Subscribed just to look for updates. That thing really is a beast. Good luck getting her running again.

Sweet system. Hope you get it working.

I'm liking this trend of these early duel socket systems resurfacing 😀
Next to no real use now but massively high end at the time, servers were rare enough let alone something like this!
Look forward to seeing it live again

I'm going to make this post here as a bit of an information post based on what I can gather from old ads and stuff, nothing at all related to repairs but some history is always nice.

So, the NCR System 3450 was originally released in Q2 to Q4 1991 or possibly even later. with a base price of $35,000 up to a top end config of $200,000 according to the Sep 24, 1990 issue of Network World. The top end config was 4x 486 DX50, 256 MB RAM, 6 GB Internal SCSI disks and 50 GB External based on this issue. Lowest end config was dual 486 DX50s, 4 MB RAM and unspecified disk. The only operating system it ran at the time was AT&T UNIX System V.

The October 21st 1991 issue of Network World actually shows a config very similar to what mine is. The config in the ad is a 2x 50 MHz 486DX, 32 MB ram, token ring controller, ethernet controller, 525 MB tape drive and 2.8 gigs of hard drive storage. All for a nice low, low price of $69,785. Mine's a 2x 50 MHz 486DX, 48 MB RAM, ethernet controller, multiprotocol adapter, 525 MB tape drive and according to the build sheet 1.5 gigs of storage. It'd probably have been very similar in price, having a bit less storage space but more ram which was equally as expensive.

This system wasn't cheap as you might be able to tell, a fair amount more than a comparable ALR PowerPro at the time. An ALR PowerPro SMP 512 with 2x 50 MHz 486, 49 megs ram, 2.1 gigs storage, dual SCSI controllers, dual NE3200 ethernet controllers and two token ring controllers was only $32,552.

A Compaq SystemPro with Dual 33 MHz 486s, 4 gigs storage, Compaq IDA controller, dual NE3200 ethernet and dual token ring was $51,272.

Later on in its life, the operating system support increased, gaining SCO UNIX support, OS/2 support (of some version or another) and eventually Windows NT. It's notable that this system is actually SMP vs ASMP so it might actually be a bit more usable with NT and OS/2 vs the Compaq System Pro which was only kind of somewhat proper under NT.

chinny22 wrote:

Next to no real use now

Gotta have them... https://www.youtube.com/watch?v=RitHgCBNrNs 🤣

Btw... did you manage to get that Novel dos share server up and running?

compgeke wrote:

I'm going to make this post here as a bit of an information post based on what I can gather from old ads and stuff, nothing at a […]
Show full quote

I'm going to make this post here as a bit of an information post based on what I can gather from old ads and stuff, nothing at all related to repairs but some history is always nice.

So, the NCR System 3450 was originally released in Q2 to Q4 1991 or possibly even later. with a base price of $35,000 up to a top end config of $200,000 according to the Sep 24, 1990 issue of Network World. The top end config was 4x 486 DX50, 256 MB RAM, 6 GB Internal SCSI disks and 50 GB External based on this issue. Lowest end config was dual 486 DX50s, 4 MB RAM and unspecified disk. The only operating system it ran at the time was AT&T UNIX System V.

The October 21st 1991 issue of Network World actually shows a config very similar to what mine is. The config in the ad is a 2x 50 MHz 486DX, 32 MB ram, token ring controller, ethernet controller, 525 MB tape drive and 2.8 gigs of hard drive storage. All for a nice low, low price of $69,785. Mine's a 2x 50 MHz 486DX, 48 MB RAM, ethernet controller, multiprotocol adapter, 525 MB tape drive and according to the build sheet 1.5 gigs of storage. It'd probably have been very similar in price, having a bit less storage space but more ram which was equally as expensive.

This system wasn't cheap as you might be able to tell, a fair amount more than a comparable ALR PowerPro at the time. An ALR PowerPro SMP 512 with 2x 50 MHz 486, 49 megs ram, 2.1 gigs storage, dual SCSI controllers, dual NE3200 ethernet controllers and two token ring controllers was only $32,552.

A Compaq SystemPro with Dual 33 MHz 486s, 4 gigs storage, Compaq IDA controller, dual NE3200 ethernet and dual token ring was $51,272.

Later on in its life, the operating system support increased, gaining SCO UNIX support, OS/2 support (of some version or another) and eventually Windows NT. It's notable that this system is actually SMP vs ASMP so it might actually be a bit more usable with NT and OS/2 vs the Compaq System Pro which was only kind of somewhat proper under NT.

I wonder if it would work with windows 2000. Might would.. since it works with WindowsNT.

I'm glad it went to a good home with an owner that will fix it up and put it to good use. Looking forward to hearing more about this project.

This is clearly the most involved 486 system I've seen. It seems like you can use a second CPU card and make this a quad-486DX50 system. Is that correct?
It would be really interesting to see how far the CPU in this beast can be upgraded. If you would like to maintain the 50 MHz bus, then perhaps a pair of Am5x86-150 CPUs on an interposer with a VRM.

Are those all EISA slots? And why does it look like the MCA card plugs into part of an EISA slot?

In theory I might be able to take it to Quad 486s. I'd need to figure out what the big backplane connector is and solder two new ones in then find another CPU and another RAM card. It'd be damn near impossible to find those, I seem to have the only one around.

These're all actually MCA slots except one special slot for a proprietary NCR video card, also impossible to find.

haha, well, I've never seen an MCA system in the flesh. They were rare, expensive, and had a short lifecycle. Hope you get this up and running.

Not heavy enough. Needs more full height 5.25" Micropolis SCSI hard drives.

It would be nice if you could find a colour matching 5.25" drive to occupy the top empty drive bay.

Everything about this system makes me quiver in my privates. It's the trifecta for me. MCA, obscure, dual cpu...

I find it rather interesting about the power supply, A 1KW supply today is probably 1/4 of the size, and can do the job at 95% efficency. I would probably re wind the choke, repair the traces and replace EVERYTHING on that board. All new mosfets, caps, etc.

This system is supported by NT 3.1 for multiprocessing, one note in the HCL though.

Only the NCR 53c710 SCSI Host Adapter is supported in this machine.

Windows NT 3.51 HCL also supports the system for multiprocessing too, no additional notes.

Windows NT 4.0 HCL lists the NCR System 3450, but using Pentium CPUs, so it may or may not work.

These systems use halncr.dll "NCR System 3000 Model 3360/3450/3550" for multi-CPU support. When you get the system running, you might have to manually select it if installing NT.

Windows 2000 will never work as it dropped Microchannel support.

feipoa wrote:

It would be nice if you could find a colour matching 5.25" drive to occupy the top empty drive bay.

Unfortunately I'd need a proprietary caddy for it, which I don't have. I did manage to find the missing blanking plate floating around inside the case though so now it has no empty holes.