My SSD Filled Up — Rethinking Where Data Goes, by Price and by Speed
18 August 2026
Data kept piling up, and the SSD inside my PC is filling up.
Local AI models alone come to 249GB. On top of that, video and photos keep accumulating.
The trouble is that SSD prices in 2026 have gone up — three to six times off the bottom. Buying more is not appealing.
So I decided to think about where data goes, from scratch. Does all of it actually need to sit on an SSD?
This article keeps what I measured here separate from what I looked up. Measurements were taken on 18 August 2026. Prices are Japanese retail; ¥1,000 is roughly $6.70.
- 1. Where can data actually live?
- 2. What is the difference between an SSD and an HDD, and why do HDDs survive?
- 3. There are three places an HDD can go
- 4. How I measured the NAS read speed
- 5. The NAS reads 1GB in nine seconds — is that slow?
- 6. Before speeding it up, I wrote down what I use the NAS for
- 7. If not speed, what is a NAS actually good for?
- 8. Only the NAS speed was measured: what this article cannot tell you
- 9. Hardware used in this article
- 10. In summary: find the narrowest point first
Where can data actually live?
Before rethinking anything, I listed what places exist. There are four.
| Place | What it is | Reachable from |
|---|---|---|
| Inside the PC | Fitted in the machine | That PC only |
| External | Connected over USB | Whichever PC it is plugged into |
| Another machine in the house | A shared folder on another PC, or a machine whose only job is storage | Anything in the house |
| Cloud | Storage a company runs, outside your home | Anywhere, including away from home |
The four above are where it goes. Separately there is what it goes on, and that is just two options: SSD or HDD.
And every one of those places can take either. Inside the PC, on the end of a USB cable, in another machine in the house. Only the cloud does not let you choose — there, the difference shows up in the price instead.
Which means you may be able to spend less without changing where anything lives, just by changing what it lives on.
The one filling up here is the first: the SSD inside the PC.
The cloud is a good option — until the capacity grows
To be clear up front, the cloud is a good option.
| What is good about it | What catches |
|---|---|
| You do not own hardware. No replacements when something breaks, no space taken up | You pay every month, indefinitely |
| It is reliable. The company keeps copies in several places and you do nothing | The more you store, the higher the monthly bill |
| Reachable from anywhere, including away from home | Cancel and you have to pull everything out before the deadline |
I looked up what two of the common ones actually cost.
| Service | Capacity | Monthly | Per year |
|---|---|---|---|
| Microsoft 365 Basic | 100GB | ¥260 | ¥3,120 |
| Google One | 100GB | ¥290 | ¥3,480 |
| Google One | 2TB | ¥1,450 | ¥17,400 |
| Google One | 5TB | ¥2,900 | ¥34,800 |
Checked on the providers’ own pages on 19 August 2026 — Japanese consumer pricing.
Three years of the 2TB plan is ¥52,200. For about that money you can buy a machine full of HDDs.
If your data fits in a few hundred GB, the cloud is the easier answer. Nothing to house, nothing to replace. It starts to weigh somewhere past 1TB.
So what does owning it cost? Comparing against a two-bay NAS
To compare against the cloud I need the purchase price. I looked at the smallest configuration.
These are sold two ways: complete, with drives already fitted, or the enclosure alone, drives bought separately. The first is cheaper and works out of the box.
| How you buy it | Rough price | Notes |
|---|---|---|
| Complete, drives included (Buffalo, I-O Data and similar) | From about ¥45,000 Two bays, 2TB × 2 = 4TB fitted | Plug it in and go. The simplest route |
| Enclosure only (Synology, UGREEN, TerraMaster and similar) | ¥30,000–¥55,000 plus drives | You choose the drives. Easier to grow later |
Street prices checked on Amazon on 20 August 2026. They move with the retailer and the date.
As above, one drive’s worth of capacity is held in reserve so the array survives a drive failure. A box advertised as “two-bay, 4TB" means two 2TB drives, and once the reserve is taken, 2TB is what you can use.
You can use the full 4TB without a reserve, but then one failed drive takes everything with it. The whole point of choosing HDDs is cheap capacity, so I am assuming the reserve is kept.
| Cloud Google One 2TB | NAS 2TB×2, 2TB usable | |
| Up front | ¥0 | ¥43,362 |
| Monthly | ¥1,450 | electricity only |
| After 1 year | ¥17,400 | ¥43,362 |
| After 2 years | ¥34,800 | ¥43,362 |
| After 3 years | ¥52,200 | ¥43,362 |
Through year two the cloud is cheaper. If there is any chance you switch within a year or two, the cloud loses you less.
If you intend to keep it three years, a NAS is worth considering — that is the size of the gap.
Stretch it to five or ten years and the NAS looks far better, but an HDD may not last that long. It has moving parts, and replacement day comes. That is why I stop at three years.
Complete, with drives fitted. This is the form the table above compares. Two 2TB drives, 2TB usable once the reserve is taken.
Enclosure only, drives bought separately. You pick the drives, which makes growing capacity later easier.
The more capacity you need, the sooner they meet
Here the difference in how you pay starts to matter. Cloud pricing scales with capacity; on a NAS the enclosure price is fixed and only the drives cost more.
The next size up is 8TB fitted (two 4TB drives; 4TB usable after the reserve).
| Usable capacity | Cloud (1 year) | NAS (one-off) | Break-even |
|---|---|---|---|
| 2TB | ¥17,400 Google One 2TB | ¥43,362 2TB×2 | 2 years 9 months |
| 4TB | ¥34,800 Google One 5TB | ¥60,280 4TB×2 | 1 year 9 months |
Prices checked 19–20 August 2026. The cloud jumps from 2TB straight to 5TB; there is no tier in between.
And consumer cloud plans simply stop. Google One tops out at 5TB; beyond that you stack contracts.
If you shoot video, keep a lot of photos, or work with large files, this is where the NAS’s cost advantage shows. If your data fits in a few hundred GB, the cloud is less work.
How many drive bays to choose: four, if you have room
Everything above assumes two bays. The number of bays changes what proportion of the capacity you get to use.
| Bays | Reserve | Fitted with 4TB drives | Usable |
|---|---|---|---|
| 2 drives | One whole drive held back | 8TB fitted → 4TB usable | 50% |
| 4 drives | One drive’s worth held back | 16TB fitted → 12TB usable | 75% |
With only two bays, keeping a reserve always costs you half. With four, the reserve is one drive’s worth out of four. The more drives, the smaller the share the reserve takes.
It does not make it faster. As this article shows, the cable is what runs out first. This is purely about capacity and peace of mind.
But do not take that as settled safety.
Second, when the NAS itself dies. That reserve only protects you against a drive failing. If the unit fails, or the room floods or burns, it does not matter how many drives survived — the data is unreachable.
Not everything needs the same level of protection. Separate what you can afford to lose from what you cannot, and protect the second group properly. That split is the realistic approach.
An example of a four-bay unit. More expensive than two bays, but holding back one drive’s worth still leaves three drives of capacity.
What you cannot lose goes on both of two NAS units
This is what I do here. Important data is written to both of two NAS units.
| A reserve drive inside one NAS | covers a drive failing |
| The same data on two NAS units | covers the whole NAS being lost |
Here there are two units: an everyday one and a long-term one. Photos and video that cannot be reshot go on both.
Writing the same data twice costs capacity, so only the irreplaceable goes on both. Everything else sits on one or the other.
How the drives are grouped (how many, in what arrangement, and why the rebuild window is dangerous) is the subject of the next article.
What you get is owning it. For something like ¥50,000 you step off the monthly payment.
For reference, putting my 59TB in the cloud would take twelve 5TB plans — ¥34,800 a month, ¥417,600 a year. The more you store, the wider that gets.
Which also means a few hundred GB is well served by the cloud. This article is about what happens past that.
What is the difference between an SSD and an HDD, and why do HDDs survive?
Before changing what data lives on, the difference. These two record data in completely different ways.
An HDD spins a platter and reads it with a head — close to a record player. An SSD has no moving parts and stores everything electrically.
| SSD | HDD | |
|---|---|---|
| Speed | Fast (thousands of MB/s inside a PC) | Slow (roughly 150–250 MB/s per drive) |
| Moving parts | None | Yes, a spinning platter |
| Shock and vibration | Tolerant | Not. Knocking one while running breaks it |
| Noise | Silent | Spin and seek noise |
| Size and weight | Small and light (some the size of a card) | Large and heavy (3.5″ for big capacities) |
| Power | Low | Higher (it keeps spinning) |
| How life is consumed | By how much you write | By how long it spins |
| Price per capacity | High | Low |
Line them up and the SSD wins on speed, silence, durability and weight. PCs moving to SSDs was inevitable.
HDDs survive on price and capacity
The gap widens with size. There are six 16TB drives in the NAS here; matching that with SSDs is unthinkable at current prices.
2. More capacity in a single unit
HDDs above 20TB are sold as a matter of course. SSDs at that capacity exist, but the price is in another bracket.
Price per terabyte is exactly why I still use HDDs. Everything else about SSDs is better, but assembling 59TB makes the difference count.
HDDs fail — you make up for it with numbers
With a platter spinning, a single HDD is a fragile thing. Which raises the obvious worry: can you trust important data to cheap drives?
So you group several HDDs so the data survives one of them failing. Here that is six 16TB drives with one drive’s worth held in reserve. One dies, you swap it, and it rebuilds.
The details of that arrangement — how many drives, in what layout, and where the danger is — are in the next article.
Which leaves the HDD with one remaining weakness: speed.
So for things you rarely rewrite — photos, video, anything you look at occasionally — is that speed something you actually need?
This state of “it keeps growing and I cannot delete it" is what pushed me to try a machine whose only job is storage. To find out how fast it reads, I measured it.
There are three places an HDD can go
Of the four places listed earlier, three can take an HDD. The cloud drops out because you do not choose what it runs on.
What I have is the third. A machine on the network like this is called a NAS, and mine holds 59TB. What is a speed of one gigabyte in nine seconds good for, and what is it not? I measured it again to find out.
How I measured the NAS read speed
A number means nothing without the conditions. Here is only what you need to reproduce it.
| What was measured | Reading one 1GB file out of a shared folder on the NAS |
| The connection | Wired, through one 1000Mbps switch. The reading PC’s port is also 1000Mbps |
| The reading side | A mini PC (Ubuntu), with the NAS mounted as a share (SMB/CIFS) |
| The NAS | UGREEN NASync DXP6800 Pro, six Toshiba 16TB drives, one drive’s worth held in reserve (close to RAID 5) |
dd if=/mnt/nas/yourfile of=/dev/null bs=1MOn Windows, copy a file of about 1GB from the NAS to the PC and divide 1024 by the seconds it took to get MB/s.
The second run onwards will read faster because the PC remembers the contents. To see the NAS itself, use the first run.
The 117MB/s here is what came out reading a 1GB file that happened to be lying around. It is not an average over repeated runs. Read it as “this is roughly what it did here".
How the drives are grouped does not affect this read speed
The arrangement above (six 16TB drives) has no bearing on this result.
As shown below, 117MB/s is close to everything a 1000Mbps link can deliver. The link runs out first, so two drives or six, the number does not change. The arrangement starts to matter only after the link is upgraded to 10Gbps.
The NAS reads 1GB in nine seconds — is that slow?
| Measured | Result |
|---|---|
| Capacity | 73TB (59TB used, 82%) Six 16TB drives, one drive’s worth in reserve. Five drives’ worth = 80TB shows as 73TB to the PC |
| Read speed | 117 MB/s One gigabyte read in about nine seconds |
| The narrowest point | 1000Mbps (the switch, and the PC’s network port) |
My first reaction was that it was slow. The M.2 drive in the PC, measured the same day, does 3,500MB/s. Thirty times faster.
Then I did the arithmetic and changed my mind.
| Theoretical maximum | 125 MB/s |
| Realistic, after protocol overhead | 110–118 MB/s |
| Measured here | 117 MB/s |
So however many drives you group inside the NAS, or whatever SSD cache you add, as long as the path crosses that 1000Mbps point, 117MB/s is where it stays.
1. the switch in between 2. the PC’s own network port
Replacing one of them changes nothing. Nor does replacing the NAS. Going faster means replacing both.
The NAS had two links ten times faster than mine
The unit is a UGREEN NASync DXP6800 Pro. Checking the specification:
| What the NAS has | What my side has | |
|---|---|---|
| Network | Two 10GbE ports | One 1GbE port |
| Other | Two Thunderbolt 4 ports, SD card reader, USB | — |
| Drives | Six HDDs plus two M.2 SSDs | — |
The NAS had two links ten times faster, and I was receiving it on one narrow one.
My first thought was to replace the switch and the network port. Then I stopped and thought about it again.
Before speeding it up, I wrote down what I use the NAS for
| What | Where | Speed | Enough? |
|---|---|---|---|
| Models currently running | M.2 inside the PC | 3,500 MB/s | Speed matters here |
| Models just being kept (202GB) | Everyday NAS | 117 MB/s | Enough |
| Video and photos (59TB) | Everyday NAS | 117 MB/s | Enough |
| Old material I no longer touch | Long-term NAS (a second unit) | Not measured | Just needs to sit there |
Writing it out made it obvious. The NAS is a place to keep things, not a place to work.
There are 202GB of models on it, but I do not run them from there — I copy them across first. I am not asking the storage to be fast, which is why 117MB/s has never been a problem.
Even replacing both ends, a 2.5Gbps PC port only doubles it. I could not find a reason to spend that on a place things merely sit.
If not speed, what is a NAS actually good for?
Three things.
1. No monthly payment
It leaves as long as you keep paying. Five years is around ¥2.09 million.
And no consumer service offers this capacity as a single plan. Enterprise archival services will take it, but many of them charge again when you retrieve it.
A NAS costs money once, then only electricity. It catches up in a year or two, and the gap widens from there.
2. When the service ends, the disks are still yours
This one made me think.
There is a NETGEAR NAS here as well, and the ReadyNAS line is discontinued. From what I could find, manufacturing ended in 2021, support ended during 2022, and firmware updates have stopped for most models.
Cloud services end. So do manufacturers. But there is a difference — and in fact, I am still using that discontinued NAS.
I demoted it. The new unit handles everyday use; the discontinued one holds long-term storage — old data I no longer touch.
Used that way, frozen firmware barely matters. It needs no new features and no speed; it needs to sit there.
A NAS admin panel is something I almost never open anyway. Put things in, take things out. A phone app covers that. The old unit included.
This does not mean the old machine is hidden. It is still on the network.
If you have an out-of-support unit sitting idle, this arrangement is a practical one. It still works as storage, so move the interface to the newer machine.
While I am here: a NAS is often assumed to mean wrestling with an admin panel, and that has not been my experience. Set it up once and it becomes putting photos and video in, and taking them out.
| A cloud service shuts down | You have to pull everything out before the deadline |
| A NAS vendor exits the market | The disks stay with you. Updates stop, but it works while it works |
It is not all upside. An unpatched machine is still sitting on the home network. Moving the interface to the newer unit does not fix that.
Keeping it unreachable from outside is still necessary. On security, a machine that still gets updates is plainly the safer one.
Even so, “what you bought does not become worthless" is a property a monthly subscription does not have.
3. You can use it without opening a PC
This one I only learned by using it.
With the UGREEN, the basic operations are done on a phone. Neither the QNAP I used before nor the NETGEAR I still have gave me that.
The other thing: with the unit within reach, media goes in over USB directly. Cards from a shoot go straight onto the NAS without starting a PC.
“SD card reader" in the specification table above is what that line actually buys you.
Across three units, ingest speed differed the most
Having used three, this is where the difference was largest.
The QNAP and the NETGEAR both read media perfectly well. It is not that they could not.
But the UGREEN uses SSDs as a cache, and ingest is markedly quicker. Push a fast card at it and it takes it without making you wait. For dumping a shoot straight in, that lands every time.
On paper it reads as one more capacity line. In practice it is a landing pad in front of the HDDs. Incoming data hits the fast SSD, and the HDDs are written behind it. So you never wait at HDD speed.
This section is an impression from use. I did not time the ingest.
I said above that storage does not need to be fast. Putting things in is the exception. If writing to the NAS is slow, you stop wanting to put anything on it.
Only the NAS speed was measured: what this article cannot tell you
Of everything above, what I measured here is the NAS read speed and the M.2 read speed, and nothing else. Cloud pricing and the NETGEAR end-of-life dates were looked up. The ingest difference is an impression from use; I did not time it.
The unit in use is a six-bay upper model with two separate SSD slots. Whether the ones I used before were of the same class — they were not.
QNAP and Synology both make models that use SSDs as a landing pad in the same way. So the honest reading is not “UGREEN is fast" but “a model that can use SSDs as a landing pad is fast".
Settling it needs two units of the same class, measured side by side. I have one of each, so this article leaves it open.
From a buyer’s point of view it may not matter which. Think of it as “choose a model that can use SSDs as a landing pad" rather than “choose that brand" and it works as advice either way.
Hardware used in this article
The NAS I measured. A six-bay unit running six Toshiba 16TB drives. You do not normally need anything this large; I chose it expecting to keep using it for a long time.
The drives inside it. Built for NAS use, designed to spin continuously.
The external SSD I use for carrying models around. It read at about 1,000MB/s here — roughly a third of the 3,500MB/s from the M.2 inside the PC. The same SSD changes a great deal depending on where and how it is connected.
In summary: find the narrowest point first
This is the thing I most wanted to write down.
Once that narrowest stretch is set, improving anything past it changes nothing. Here, the NAS had two 10Gbps ports while the switch and the PC port ran at 1000Mbps, and that is where it stopped.
The cloud is no different. Whichever service you choose, it cannot beat your home connection. Before comparing services, find the narrowest point in your own house.
Then, once you know where it is, the next question is whether widening it is worth it. Here it was not. A place things merely sit does not need to be fast.
The simplest way to apply this to yourself
If you are worried that HDDs will be too slow, ask yourself whether your current cloud storage bothers you.
So if cloud speed is not a problem for you, a NAS full of HDDs will not be either. If anything it can be quicker, since it never leaves the house.
The worry that “HDDs are slow" usually never surfaces — something narrower comes first.
What I found here
- The NAS measured 117MB/s — 93.6% of theoretical for a 1000Mbps link. It is using the link up
- What is slow is the cabling, not the HDDs. The NAS had two links ten times faster
- But storage does not need to be fast. What runs, runs off the local SSD; what is kept, sits on the NAS
- 59TB in the cloud works out at ¥417,600 a year. A NAS costs once, then electricity
- What survives the ending differs. The cloud has to be evacuated; with a NAS the disks stay
- Two units, split by role. The new one for everyday use, the out-of-support one for long-term storage, reached through the new one’s app
- Ingest speed seems to come down to whether the model can use SSDs as a landing pad. Whether that is a vendor difference or a tier difference, this article cannot say
I started because SSDs got expensive, and ended up at a question about where to put what. Not everything needs to live somewhere fast.
Next comes what goes inside: RAID, the scheme for grouping drives, and how an SSD’s internals change both its speed and its life. Buy without knowing that difference and the cheap purchase turns out to be the one that dies early.










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