leeter

There are tricks. I've been through such an acquisition. The purchaser sets up a new "Philz Coffee Co LLC" then purchases assets and operations for the exact amount the preferred stock holders want. They then liquidate the old company. Because the old company was never legally "bought" the common stock holders are SOL because they now own stock in a fictional company. That's not to say they don't have options... but I am not a lawyer and that definitely involves lawyers.

There is already a project to handle this because this has already happened to so much hardware https://theretroweb.com/

> but practically useable operating systems in the traditional sense of abstracting away real hardware can still be counted on one hand.

I think this is telling. There are plenty of 'standards' for interfaces in the hardware world. Some (mostly USB) are even 'followed', but the realities of hardware are that it never behaves nominally. So without someone willing to spend the time writing code to handle the quirks that can't be patched out and the errata it's very hard to run on physical hardware with any performance or support.

I did see that and for people that need that specific functionality it seemed like a good solution.

My goal was more "What if DOS hadn't ended and but kept up support for modern hardware" along with emulation of common things in DOS gaming. So for example you would be able to set up a PIV that mapped certain resources directly or emulated them depending on the need.

Could I use DOSBox for this... yes, but this is a "why not" sort of thing. I figured it would be a good excuse to learn OS dev. But life has kept me busy for now.

Correct, there is a difference between MS-DOS and IBM-PC compatible and a DOS (ex: all the DOSes that existed for Amiga/Apple II/Commodore etc). There are many DOSes (and even MSDOSes, because yay early PC era incompatibilities!), but there is a very dubious list of things needed to be MS-DOS and IBM-PC compatible. You can probably do it if you're willing to setup a hypervisor and emulate some hardware.

NGL one of my long term projects was/is something exactly like this but UEFI and secure boot. The idea being to use the VM extensions to create IBM-PC and DOS compatible environments. For anything using DPMI[1] I'd probably do the same trick as Win95 did and just replace it with my own implementation so it's not too overburdened with layers.

[1] https://en.wikipedia.org/wiki/DOS_Protected_Mode_Interface

It's a complicated space. There are attacks on both maintained and unmaintained stacks. There are definitely attacks against windows 95/98 too because people have things like mills or other industrial automation that are powered by those OSes still connected to the internet. There is a lot of SCADA[1] too that fits that bill. It's easy to think "but why wasn't this replaced!" and the answer is almost always "cost or process certification". If the operator is lucky and has good networking folks all of this is in a very very well firewalled VLAN. But, never underestimate the amount of people that are not that savvy and just have it plugged into the internet.

For anyone saying these aren't targets, no they are probably already hacked. These are the things that keep the national security folks up at night knowing an adversary has them already backdoored and set up for take down. Moreover if they execute on that they would go for maximum damage first to either create chaos, or prevent the system from being repaired easily.

[1]https://en.wikipedia.org/wiki/SCADA#Security

You attack the networking stacks for it, those are still actively developed (mTCP was last updated Jan 2025) as businesses use networked DOS for quite a few things. A DOS networking stack consists of a packet driver, a NIC driver, and a protocol library. All of those have attack surface. NIC drivers in particular often haven't really had updates since they were first released. Because for hardware manufacturers of the time the goal was on getting people to use the hardware, not on supporting them. There are newer DOS NIC drivers than you'd think too. Realtek last I checked still makes and supports an ISA NIC.

So Epictronics recently looked at the 386SX, the version with the 16bit external bus, which was slower than the 286 at the same clock. What changed between that and this? Was the major difference the double clock hit on fetch? Or did it have a shorter prefetch queue as well like the 8088?

Not just that. Most operating systems lie about when an IO transaction completes for performance reasons. So if you lose power or the IO device dies you still think it succeeded. A mainframe doesn't do that... it also multiplexes the IO so it happens more than once so if one adapter fails it keeps going. The resiliency is the main use case in many situations. That said IME 99.995% of use cases don't need a mainframe. They just don't need to be that reliable if they can fail gracefully.

Related: Union Pacific fitted 4014 with Positive Train Control, the US version of this tech https://www.up.com/aboutup/community/inside_track/big-boy-te...

They are/were also planning on adding it to 844 too.

I'm apparently off by a factor of ten, but then again I'm including the fuse... which probably does cost the other 18k. I've updated my post to include that to make the distinction.

IMHO: Yes, subs are great when you need people to constantly be looking over their shoulder and spending tons of money on ASW. They are great at interdicting logistical shipping too. But, they are really really bad at being seen (that's kinda the point), and sometimes you want a unit to be seen to force an enemy to dedicate forces to take care of it. Look at the amount of forces the allies dedicated to sinking Bismark and Yamato. In both cases a not insignificant amount was dedicated to taking down a battleship and even then in both cases not without either significant losses on the allies side, or overwhelming force and waiting for the battleship to be uncharacteristically exposed.

Surface vessels can also provide direct fire which is actually a lot cheaper than a torpedo. The cost of a 5" shell is something like ~20k (2k per actual shell + fuse which I assume is at least 18k) vs $5.39M(2022, source wikipedia) for a MK48 torpedo. 5" gun mounts are pretty much fully automated at this point, they have places for sailors for emergency... but on a NOMARs ship you'd just YOLO on that and use a simplified version without the manual backups for weight savings.

One of the coolest things about this is not this operating on it's own, but operating with a larger manned surface vessel or sub. They act as a cheaper and disposable escort for a much more powerful vessel creating a force multiplier. This is pretty much identical to the "Loyal wingman" that has been under development for awhile.

TLDR: there is value in having a ship being a visible target and having a gun. There is also value in having both NOMARs and manned ships working together.

> You contribute some % of your paycheck and your employer matches some amount of that (potentially with a vesting schedule)

This is actually completely optional, many employers do not. For example mine does not do any matching or contributions

> The money can be invested, and then at some age (55.5 i believe?) you can access the money without being taxed. There is a maximum you can contribute per year etc etc.

So the tax side of this depends on if the 401k was done as Roth or traditional. Traditional IRAs are tax advantaged but not tax free. Contributions are pre-tax from the employee's paycheck. Roth on the other hand is post tax and tax free on withdrawal (assuming no penalties).

Yeah I realized that was the worst way to go about testing that anyway right after I went to bed last night. If (big stress on if) that was the issue a ferrite bead would be a better way to test it. Based on what you're saying my SWAGs were wildly off. I'd still like to see the sims of it however to see if they provide any illumination on the issue. What makes me think something weird is going on is that it's two out of six wires heating up to absurd degrees. Of the other four two are carrying normal currents and the last two (based on Roman's video) are carrying practically nothing. Buildzoid makes the convincing argument that clearly Nvidia engineers were aware of something like this could happen on the 3090. But, then didn't carry that over to the 4090/5090.

I'm curious, if there are any high level electrical engineers reading this please respond.

I wonder if that vertical (as far as the PCB goes) power connector will always ensure that this sort of imbalance will always occur. While we like to pretend that current is even in any given current plane that's not what happens. The impedance of the wires and copper is not perfectly ideal. This is why these connectors have equal number of grounds, so they have an ideal shortest path and balanced return current path. So I'm curious if electrically it's just impossible to have a vertical connector like that (on that shorts all the pins for 12V together instead of current balancing them) and have it balance current across the pins. The pins closest to the board should in theory have the greatest currents as they are the shortest path electrically. Based on the pictures that appears to be the case. It appears that the pins under the most stress are likely those with the lowest impedance.

Assuming my SWAG above is correct... I'm curious if this is affected by the per pin impedance on the PSU too. Where if certain folks are just unlucky get a situation where some pins in the connector have a significantly lower impedance than the rest.

If my second SWAG is plausible, my third and really bad SWAG is that removing the two ground pins nearest the PCB could actually "balance" the current better by forcing the current to use a slightly longer path for the power pins. But, my guess is this will just cause EMI issues. So please don't test this unless you're an EE and know what you're doing.

This is pure speculation on top of what Buildzoid, the posts above this have said, and what I've learned from Robert Feranec's videos. I'm in no way an electrical engineer, just a humble hobbyist and person that loves to learn.

Honestly with 50A of current we should be using connectors that screw into place firmly and have a single wipe or a single solid conductor pin style. Multi-pin connectors will always inherently have issues with imbalance of power delivery. With extremely slim engineering margins this is basically asking for disaster. I stand by what I've said elsewhere: If I was an insurance company I'd issue a notice that fires caused by this connector will not be covered by any issued policy as it does not satisfy reasonable engineering margins.

edit: replaced power with current... we're talking amps not watts

Alternatively there is everybody's favorite CreateThreadpoolTimer https://learn.microsoft.com/en-us/windows/win32/api/threadpo... now that the threadpool is active on any Win32 process by default AFAIK. But for something you don't mind blocking the above is often easier to use.

To add to this and to quote a friend who has more NDAs in regards to microarchitecture than I can count and thus shall remain nameless: "You can have a fast CPU or a secure CPU: Pick one". Pretty much everything a modern CPU does has side effects that are something that any sufficiently motivated attacker can find a way to use (most likely). While many are core specific (register rename, execution port usage for example), many are not (speculative execution, speculative loads). Side channels are a persnickety thing, and nearly impossible to fully account for.

Can you make a "Secure" CPU? In theory yes, but it won't be fast or as power efficient as it could in theory be. Because the things that allow those things are all possible side channels. This is why in theory the TPM in your machine is for those sorts of things (allegedly, they have their own side channels).

The harder question is "what is enough?" e.g. at what level does it not matter that much anymore? The answer based on the post above this is based on quite a lot of risk analysis and design considerations. These design decisions were the best balance of security and speed given the available information at the time.

Sure, can you build that theoretically perfect secure CPU? Yes. But, if you can't do anything that actually needs security on it because it's so slow; do you care?

I think a lot of very accurate reasons have been covered by others. These are my key points:

* COL in most areas has skyrocketed, housing and healthcare have both ballooned in cost massively. This has meant I'm much less likely to take risks that would put either of these at risk.

* My ideas aren't unique. I'm 99.9995% sure that the ideas I have floating around in my head for a startup are already covered by someone much more capable than I to execute them. Given that the main reason startups fail is a lack of market, and I'm definitely not the sort of person that can just make a market appear overnight... Yeah definitely not feeling like taking a risk on something likely either already served or which needs someone who can communicate to prospective customers why such a market should exist.

* I'm not interested in cashing out. My goal if I'm growing a business is to have something I enjoy and cherish. Not just to sell and cash out. (I say this now naively )

TLDR: The risk reward ratio in my estimation only favors the ultra wealthy, or unicorn engineers right now. I'm smart but I'm not that smart. My goal right now is to get enough money I can retire and work on projects I want to. If that means one of them becomes a startup, I'm good with that. But, I'm also not expecting to IPO or get VC backing if that happens.

At least where I am, I would attribute it to code requirements. A livable attic requires much more work to meet code than a vented attic space. Not to mention the energy cost of having a livable attic can be higher because there is no venting and limited insulation. All of this is speculation of course. You definitely could do it. But, if you did you'd almost certainly have to use more expensive construction techniques to meet code insulation requirements.

Sucker's bet. They almost certainly do. The question is more would the homeowners have actually been better off if the homes were more damaged requiring being rebuilt? Based on anecdotes from the Hawaii fires... the answer is: Maybe. Combustion products are notoriously hard to remediate. Just living in those houses post fire could be the equivalent of giving yourself smoke inhalation issues.

This makes me want to have someone make a "Consultomancer" as a class just to read the spell descriptions.

So the interesting thing about that is there is now a dedicated team of enthusiasts porting and cloning cards on MCA[1]. Still not cheap... but at least you can get a sound card now.

[1] https://texelec.com/product-category/mca-bus/

I'm curious about this exact sort of thing in regards to windows 98 and how hard it would be to support DirectX given that 3D support code is visible in Mesa3D for reference. But, then again... I'm one of the loonies that likes to see how far one can push an old operating system on new hardware.

So awhile back I was working on a chaotic renderer. This let me to a really weird set of situations:

* If the GPU is a non-dedicated older style intel GPU, use CPU

* If the GPU is a non-dedicated anything else do anything super parallel on the GPU but anything that can be BRRRRRT via CPU on the CPU because the memory is shared.

* If the GPU is dedicated move everything to GPU memory and keep it there and only pull back small statistics if at all plausible.

Wow... I haven't heard of someone using refresh timing to speed up a system outside of retro hardware in ages. I guess I'd just assumed that after we'd transitioned to DDR that refresh cycles were just such a small part of overall cycle time that it didn't matter. Goes to show what I know!

> Today I still work in hardware, but mostly with digital circuits. While my analog knowledge has decayed over the last decade, that project and it's success gives me great confidence any time I have to deal with the domain.

Do you think about the analog qualities of your traces when laying things out? If so then the course was well taken.

In my observations I've found that too many digital engineers assume a differential pair will save them without actually fixing the impedance and parasitic issues. Particularly as the timings of things become so much more precise analog is so important. People forget that a digital circuit is just an analog one under the covers.

AFAIK they are required to use very specific certified parts. So while they could in theory use motherboard replacements cleanly I believe that's prohibited because they haven't undergone certification. That said... I think this is very valid and a company that made extremely high quality parts for this purpose could serve both. But, it would mean getting a modern board through FCC and cert and that is an extremely non-trivial process IIRC. If I was going to go down that route I'd reach out to the utilities to see if they will fund it.

Sadly no, and (IANAL) the law here is clear AFAIK. Money cannot be spent outside of what it was allocated. Firefighting I'm given to understand explicitly excludes prevention. This might be one of the most short sighted budget allocations I've ever seen. As a dollar spent on prevention easily covers 10 on fighting.

I didn't check the date on mine... but also a Sony Dream Machine. Probably same or similar vintage.