Hacking Windows NT 4.0 SMP for more than 2 CPUs

While trying to index a massive dataset, I found that the whole AltaVista process was kind of slow. And what better way to hope to speed it up, than to add some more processors. The catch is that the indexer only works on the Workstation SKU, and as such it’ll limit you to two processors. But what if one of those ‘one simple trick’ tricks actually can unlock all your cores?

From Rairii:

load the registry hive setupreg.hiv from i386 folder
in ControlSet001\Services\setupdd
default registry value
at offset 8, replace the value thats there (probably 00) with 20, ie decimal 32
then when reinstalling it should set up the registry to allow 32 cpus
ControlSet001-Services-setupdd

I didn’t want to bother trying to make a ‘correct’ NT 4 CD, so I just did the dos bootable disk image thing, and the old school “winnt /b” setup from within DOS on VMWare Workstation 17, and yeah behold!

NT 4.0 Workstation on VMware Workstation Pro 17

Although I should add that it’s not all sunshine and rainbows, it fails to boot about 50% of the time with a stop 0x00000078 PHASE0_EXCEPTION. I don’t know what is up with that, if it’s my AMD processor, something with VMware…

PHASE0_EXCEPTION

Sadly, for anyone wondering, it didn’t help my use case. The fundamental issue being that AltaVista tries to actually use filters to interpret the data, and Microsoft Word documents with the .txt extension, or anything with 90’s L337 ascii art just straight up trip up the indexer halting all progress.

ASCII ART BAD!!

Obviously, this is building up to something else, something I think is kind of exciting, but even as a ‘distraction’ adding more cores to NT 4.0 Workstation is always a good thing!

Scored what I hope is an awesome motherboard for $30

I saw this great board online carousell, on some local seller board. Although eBay may be the defacto site for buying old garbage, keep an eye out for local stuff too. There is craigslist in the USA & Kijiji in Canada.

Intel l440gx+

Yes, it’s an Intel l440gx+, a dual processor motherboard, with an ISA slot! I’m pretty sure it’s all 5v PCI slots, but who knows. And at $250 HKD, much cheaper than the ones on eBay. Although condition is pretty much unknown.

Pentium III 750Mhz

And it has two Pentium III’s clocked in at an amazing 750Mhz. It’ll make a great MS-DOS box for sure, with plenty of punch. Along with being great for Windows NT 4.0

I think it may have 128MB of RAM as well. Not great, but it’s still pretty good.

Being this old also means it most certainly is MP 1.1 compatible, as I just found this mp_v1_1.c lurking in the OSFMK used in the ancient/abandonded mach kernel for MkLinux. Of course half the fun will come in trying to build the kernel from source (can’t find any intel binaries), and seeing if this old board works.

Of course getting the board was a mission in itself, as I had to cross through one of the big protests last night to get it. I took some video of it on my way back, and walked up to where the front line was going to be.