More (perhaps unnecessary) detail:
In a few months I'll probably be moving. Everything will be shipped in shipping containers that are packed by us and collected and shipped by truck. They will likely spend time in warehouses at one or both ends of the trip. Let's assume everything is in those shipping containers for 1.5-2 weeks. A humid environment is likely.

I have a lot of old PC hardware and while I may get rid of some stuff, I'm going to have a lot to move. It needs to be packed efficiently, but there are some items that I'm especially anxious to not have turn up dead at the other end of the trip.
I plan to stuff all PC cases as densely with hardware as possible. In most, I think I might remove heatsinks/etc and stack the case full of motherboards (in static shielding bags). In some cases I might instead have 1 motherboard screwed into the case with expansion cards either stacked loose(bagged), or installed in the slots. Is stuffing the cases this way asking for disaster?

For the most valuable motherboards - are they safer if screwed into a case or if bagged loose, maybe stacked 2 or 3 high in a cardboard motherboard box?

For a valuable card, is it safer for the card to be screwed into a case and installed in a slot? Or in a static shielding bag loose?
I'm inclined to think that screwing cards into a case could subject them to vibration and small amounts of flexing whenever the shipping container hits a bump.
Is a card more immune to ESD when installed in a slot? Or is a shielding bag better?

I have CPU trays but I'm not sure how I can assuredly keep them clenched tightly together so the CPUs don't spill out.

My biggest quandry is probably hard drives. Is a hard drive safer when installed in a case, or when boxed?
My main concern is 7-8 large modern hard drives in a file server. I could remove all the drives and pack them in a box, or I can leave them installed in the case. I don't know which is safer.
I have other hard drives, but these are the most concerning since data is at risk if I lose more than 2 of them, and they are the most expensive to replace. I will have a backup of the most critical data, but the rest of it relies on double parity (SnapRAID) due to the impracticality of making a 1:1 backup of all of it.
If the answer is box, I have a limited number (not enough) of foam shipping containers, but they take a lot of space per drive. I also have those plastic clamshells that drives sometimes come in.
My remaining bulk of hard drives will have to be piled pretty close together with some bubble wrap, I can't be too generous to them due to how many "miscellaneous" old drives I have.

Curious what anybody's experiences have been with transporting your hardware in bulk. Did anything turn up dead? Anything you think you did right or wrong?

I just put everything in bubble wrap and boxed them. They were fine.
You are overthinking it.

I hate moving!!! I've moved a LOT!

shamino wrote:

When shipping computer hardware, particularly with concern for the most valuable components - is it safer for the parts to be installed in cases, or is it safer for them to be bagged and stacked loose in a box?

In the cases with the hard drives removed.
Hard drives need packed well enough to resist shock/vibration from bumpy rides in trucks.
Loose boards and parts just need packed in a box like anything else fragile.
(You can use the empty space in cases to pack some of that.)
For LCD monitors my preference is to cut a piece of hardboard and tape it over the glass. It flexes less.

shamino wrote:

For valuable parts, is it better to fight humidity with dessicant packets, or is high humidity fine?

Rice in fine net bags or multiple wraps of cheese cloth. It's cheap and it does the job.
Cheese cloth doesn't always go well. Usually at least some gets out because the fibers aren't fixed.
If you HAVE to you can make the bags out of old cotton tee-shirts and staple the bags closed.
The cotton won't breath as well as a mesh but it's good enough.

shamino wrote:

Let's assume that upon arrival, parts are allowed to acclimate to their indoor environment for at least a few hours before powering them.

The need for that will depend on the weather.
If you aren't sure there is no condensation then leave them with the covers off (for air flow) overnight.
You will need the covers off anyway to put the drives back and check for cards and RAM that rattled loose.
If you HAVE to have one running right away then blow air into the open case until the surface temp matches the rest of the room.
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Heavy things in a box of loose peanuts will move through the peanuts (like a rock through water) and end up with one side against the inside of the box (or at the bottom) and unprotected from a drop or a smack.
To minimize that movement use some large chunks of styrofoam -or- bubble bags -or- smaller boxes filled with peanuts -or- empty water bottles with the caps back on -or- fashion some bubble wrap into tube like rolls and tape them to stay rolled. (I tape whatever to the inside of the box.) Then fill the remaining empty space with loose peanuts.
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As long as things cannot move around and rub against each other things will go fine.

I hate moving (I've done it a lot, but thankfully not for the past 10 years).
Most of my hardware is stored in plastic storage boxes, the kind with locking lids. I keep them packed all the time except for 1-2 systems which I have out and working at a time due to lack of space. The boxes are packed as if ready to move at any time. I line the inside of the boxes with aluminum foil to avoid static. Each type of component goes in a different box. I also place layers of aluminum foil between the components. I generally leave the CPUs in the motherboards but remove the heatsinks and pack those in a separate box. Memory also comes off and is packed separately. I try to pack everything in each box so they can't move inside if shaken: fill empty spaces with fillers such as crumpled newspaper.

If you're worried about humidity I recommend that you put one of these in each box: https://www.eva-dry.com/product/e-333-renewab … e-dehumidifier/ They contain silica gel beads to absorb moisture, and are easily recharged by plugging them in a power outlet (they have an internal heating element that makes the absorbed moisture evaporate). Don't buy directly from their website though, you can find them much cheaper in other places like Amazon. Based on my experience one of these is enough to keep the contents of a storage box dry for a few weeks if tightly closed and not opened for the duration.

stamasd wrote:

Most of my hardware is stored in plastic storage boxes, the kind with locking lids.

Yes. I've been transitioning from cardboard boxes to those myself.
Sam's club put their 27 gallon (black-yellow) on sale last week and I bought 40 more. I'm up to around 100 now.
In about 2 years I have to move to another State to take care of an elderly relative.
(My brother has it covered for now but he will have to move for work by then.)

I will be spending the next 2 years selling like crazy to get the collection size down.
The goal (that I will never make) is to get rid of 95% of it.

Not exactly space conservative but I've found pizza boxes (cheap bought in 50 packs) work great to keep things organized inside the boxes.
The 12" will hold full ATX boards if you trim the flap to clear the PCB when it's closed.
The 10" work for most BAT and uATX and some longer cards.
The 8" work well for most add-in cards, collections of RAM and some CPUs.
HDD blister/clamshells also work well for collections of RAM.
I put the parts in anti-static bags and use pink bubble-wrap to keep things from shifting inside the pizza boxes.
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ESD safe foam, ESD safe bubble wrap, anti-static bags. Place in cardboard boxes with additional bubble wrap or foam layers. Protect boards/cards/etc from bumping into each other. Desiccant really isn't necessary for moving on a short trip. That would only be necessary for long term storage in a sealed container.

I wrap mine is space age, top secret, government issue, material, that was manufactured in a ISO cleanroom then blessed by a priest with holy water. Then I know its safe. 🤣

If the lot is going to be sitting on a cargo ship, I'd probably seal the stuff up, even if it may lead to some condensation, especially for the rarer items. I wouldn't want several of my rarer items being exposed to salty air for 3 months on a boat. Another idea is to use "space bags" for some items. These are very large and thick plastic bags, about the size of a suit case, which contain a check valve to let you suck the air out using a household vacuum. This should reduce condensation inside the bag. I've had some space bags in the past and most of them would usually keep a vacuum seal for a few months.

Static bags for cards and drives, generous amounts of bubble wrap.

I've sold and shipped desktop towers with those fragile tempered glass side panels and never had an issue.

Remove all the expansion cards, motherboard, drives, etc from the case, put back any bay covers etc that came with it.
Pack the components in anti-static bags, and seal them. I use a heat-sealer, but tape is fine too.
Wrap them up in bubble wrap and/or foam. Remove the heat-sink from the motherboard/processor. You can generally leave the processor in. RAM should be fine too, unless it has large heat-sinks and wrapping the Mobo would put strain on the sockets.

Once everything is wrapped up well, stuff it inside the computer case, and fill any gaps with more bubble wrap or foam. You want to make it so nothing is rattling about inside.

If you have the original case box, put the case in there. They were made for shipping, and it'll do great. If you DON'T, get a box that is larger than the case and can pack the case horizontally. Put an expanding foam pack on the bottom and activate it, then press the computer case into it and hold it down until finishes expanding. Make sure it's covering the CORNERS of the case and has expanded up the sides a bit.

You can then use another expanding foam pack on the other side, and seal/hold the box shut as it expands, or just stuff it with more bubblewrap/foam.

This is a foolproof shipping method, and will protect it from even the roughest shipping. Expanding foam packs are godlike. I use them for shipping CRTs, and they never fail.

To be honest never had an issue with shipping PCs with all components inside... so YMMV