POLARISAI ACADEMY

Create a listing

A listing says what hardware you have, or what you want to buy, in enough detail that a stranger can judge the deal. The market has no listings yet, so you cannot post today; these are the steps the free form will ask for, and the notes you can write down now.

Create a listing

Hardware listings open with membership. No listings have been published yet.

Market rules

Beginner

Four steps, then stop

A listing is a public note that you have hardware for sale, or that you want to buy some. The Polaris market has no listings yet. When it opens, posting will be free. The form will use four steps and check the fields as you type.

Step one is choosing a template. The Help getting started template is a plain description of what you have or need. Graphics card for sale asks for the card name, the memory, and the price.

Step two is the condition: what works, what fails, and how you used it. Sweden's Sale of Goods Act (köplagen) says the goods must match what the seller said. If you sell the card as is, you remain answerable for a serious fault you knew and hid, and for goods in much worse shape than the price suggests. The Swedish Consumer Agency says to examine the item, and always to examine it when the seller tells you to.

Step three is photos you took. Put a handwritten slip in the frame with your name and the date. Photograph the serial number. Add a screenshot that shows the card recognized and working.

Step four is price and handover. The Swedish Police tell private buyers to avoid paying before they hold the item, and to meet in person. Refuse a buyer who demands a special courier fee, and refuse every link that buyer sends. A bid is not binding. Write two identical agreements. Both people sign both copies and keep one each, with names, item, condition, price, and payment.

Draft a first listing from my notes

Help me write a private-sale listing for computer hardware. Ask me one question at a time until you have: what the item is, what works, what is broken, how I used it, the price, and the city where we can meet. Then draft four short paragraphs: the item, the condition, what the photos show (a handwritten name-and-date slip, the serial number, a screenshot of the card working), and the handover. Use only facts I gave you. If a fact is missing, write UNKNOWN. End with a reminder to meet in person, to avoid paying before handover, and for each of us to keep a signed copy of the same agreement. Do not invent prices, dates, or test results.

Intermediate

The facts that decide fit

These fields tell a buyer whether the card fits the computer and the model. Read them off the card, the box, or the maker page: memory in gigabytes, power in watts, age, form factor, and whether model weights remain on the disk.

Card memory is called VRAM. Weights are the numbers a model learned. Four-bit weights, labeled Q4, take about half a byte per parameter, so a 70-billion-parameter model needs about 35 gigabytes for the weights alone, before memory for the text it holds. If you ran a named model, write its name and the quantization. Keep a number you measured separate from a data-sheet figure.

Power means the watt figure plus the plugs the card uses. Age is the purchase year. Form factor is the shape: slots, length, and whether the cooler blows out of the case.

For a whole workstation, add the motherboard, the PCIe lane count of the slot, and the cooling. PCIe is the link between card and board. A slot with fewer lanes than the card was built for still runs it, and moves data more slowly.

Name any weight files left on the disk, and say whether you will wipe it before handover. Wipe it unless the buyer asked to keep the files and you are allowed to pass them on.

A wanted ad can state a budget for a part, or for someone to assemble a machine. In Sweden, the Tax Agency treats money you are paid for doing a task as payment for a service. An occasional sale of your own used goods follows the capital-income rules.

Turn my notes into listing fields

Turn my notes into listing fields for a used graphics card or a small AI workstation. Ask for any of these I have not given: VRAM in GB, power in watts, power connectors, year of purchase, form factor (slots and length), motherboard, PCIe lane count, cooling, model weights still on the disk, and my budget if this is a wanted ad. For a 4-bit model, estimate weight memory as parameters times 0.5 bytes, and say that running the model needs more. Mark every number I did not supply as UNKNOWN. Do not look up a catalog spec and present it as my measurement. Explain any term I ask about in one plain sentence.

Expert

Peaks, links, licenses, fingerprints

Write a figure only when it comes from the vendor data sheet, your own screen, or a checksum.

FP8 and FP16 store a fractional number in 8 or 16 bits. A TFLOP is a trillion arithmetic steps per second. The peak figure on a data sheet is the best case for one kind of calculation, not what you will see in practice. Write the peak with its format, and write any speed you measured with the tool and the model.

Memory bandwidth, in gigabytes per second, is how fast the card reads and writes its own memory. A model too large for that memory waits on slower storage. NVLink is NVIDIA's direct link between cards. Write how many connectors there are, and whether the bridges are in the box.

A wanted ad states the gigabytes the job needs, the model name, the quantization, and the context length, meaning how much text the model holds at once.

If the disk holds a model or a dataset, name the license with an SPDX identifier when the Software Package Data Exchange lists one. MIT and Apache-2.0 are on that list, and Apache-2.0 includes a patent grant. OpenRAIL-M allows sharing but forbids the specific uses listed in the license. Read that list, then copy the license, the training data, and the limits from the model card.

Add a SHA-256 checksum for each file. The checksum is a fingerprint of the bytes. The buyer runs the same sum and compares.

Posting will be free. The price can change later. The description locks one day after publication. A bid binds nobody. The two signed copies are the sale.

Review the numbers, the license, and the checksums

Review this hardware listing before I publish it. Check that every performance number names its source (data sheet or my own run), its number format (such as FP8 or FP16), and its unit (TFLOPS or GB/s). Check the NVLink connector count and whether bridges are included. If model or data files are included, require an SPDX identifier or a link to the full license, and if the license is OpenRAIL-M tell me to paste the use restrictions. Require a SHA-256 checksum for each file. List every gap as a bullet. Do not invent specifications.

Checklist before you hand anything over

  • The thing for sale is in your hands, or the ad is a wanted ad with a budget and a memory figure.
  • Your photo shows a handwritten slip with your name and the date, in the same frame as the hardware.
  • Another photo shows the serial number.
  • A screenshot shows the card recognized, with the name of the tool visible.
  • The condition lists faults you know: crashes, coil whine, a replaced fan, a repaired board.
  • Memory, watts, age, and shape are filled in, or marked unknown.
  • Weight files are named, or the listing says the disk will be wiped.
  • A license is an SPDX identifier, or a link to the full text. OpenRAIL-M includes its list of forbidden uses.
  • Every file you pass on has a SHA-256 line.
  • The price is the price on handover. The listing asks for no payment before that.
  • You can meet, or the agreement says who carries the risk if a carrier takes the card.

Two signed copies, and the Swedish tax line

Write two identical copies. Both people sign both, and each keeps one. Include the full names, what is sold, the condition, the price, how and when it is paid, and where it is handed over. The Swedish Consumer Agency recommends that list. Sweden gives no automatic right to change your mind on a private purchase; a right to cancel exists only if you both agreed to it before paying. A maker's warranty often stays with the person who bought from the company, so read the warranty terms.

On tax, if the sale is in Sweden: an occasional sale of your own everyday things is declared only for the part of the profit above 50,000 kronor, as capital income. Selling the same sort of goods often can be a hobby or a business. Hobby surplus is taxed as employment income, and you keep the records for seven years. Money someone pays you to do a task is a gig, which the Tax Agency treats separately from a hobby. Outside Sweden, use your own tax authority's rules. These pages are summaries of public texts, which remain the property of their publishers.

What opens with the market

When the market opens, a listing will be free. The form will check fields while you type. You can change the price after publishing. One day later the description locks, so a reader can trust the wording they already saw. A bid binds nobody until both signed copies exist.

The form will refuse three kinds of ad: one that asks for money before the handover, one that claims to sell hardware and has no photo of that hardware, and a file offer with neither a license nor a checksum. A model or a dataset belongs in the ad when it is on a disk you are selling, or when a wanted ad says how much memory the job needs.

A shared community DGX Station would give the buyer and the seller one known machine on which to check the card's memory, link, and cooling against the listing before any money moves. About the shared station

Sources

  • Buying from a private individualSwedish Consumer Agency, in English: examine the goods, write two signed copies, and what a buyer can still claim when a private sale goes wrong. Proofread 9 April 2026.
  • Sale of Goods Act (köplagen, SFS 1990:931)The statute. Section 3 lets a written contract replace the default rules. Sections 17 to 20 say when goods are defective, including a sale described as as is.
  • Advert fraudSwedish Police guidance: meet and take the item, avoid paying a private seller in advance, ignore courier-fee demands and links from a buyer.
  • Selling and renting out onlineSwedish Tax Agency: on an occasional sale of personal belongings, declare only the profit above 50,000 kronor, as capital income. Regular selling is taxed differently.
  • HobbyHow the Tax Agency separates a hobby from a business, and why a paid gig is declared on its own. Hobby records are kept for seven years.
  • SPDX license listThe Software Package Data Exchange identifiers. Look up MIT and Apache-2.0, and use the short identifier in the listing.
  • Model cardsWhat Hugging Face expects beside a model: intended use, training data, evaluation, and the license name in the card metadata.
  • OpenRAIL licensing frameworkHugging Face explains OpenRAIL and includes BigScience OpenRAIL-M as an example.

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