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Why are RAM and phone prices rising? DRAM, HBM and AI memory, explained.

Oct 13, 2026 · 8 min read · by ElectroCalc

AI is competing with your phone for memory chips. Here is what RAM, DRAM and HBM mean, why prices are climbing and how to work out how much memory an AI model needs.

Quick answer

AI is soaking up memory chips, and that pushes up prices for everyone. You can check how much memory an AI model needs with one simple sum.

  • Memory (GB) ≈ billions of parameters × bytes per parameter
  • A 7 billion parameter model needs about 3.5 GB at 4-bit and 14 GB at 16-bit.
  • RAM is fast working memory. Storage is slow long-term memory.

Why everyone is talking about memory prices

Phones, laptops and gaming PCs are getting more expensive, and memory is a big reason. News reports this month describe AI companies competing hard for advanced memory chips, while phone and PC makers still need ordinary DRAM and storage. When demand jumps and factories can't keep up, prices rise. One report even described a memory squeeze that is rewriting the economics of the chip industry.

RAM, DRAM and storage: what is the difference?

These words get mixed up. Think of a desk and a filing cabinet.

Chip cache tiny, fastest RAM (DRAM) working memory, 8 to 128 GB Storage (flash) keeps files, 128 GB to 2 TB Higher = faster and smaller Lower = slower, bigger, cheaper per GB
The memory ladder: the closer to the chip, the faster and smaller the memory. Learn more about RAM.

Why AI eats so much memory

A large language model is a huge list of numbers called parameters. To work quickly, all of those numbers must sit in fast memory at the same time. A faster chip doesn't help if the model won't fit. This is why AI laptops advertise big memory, such as 128 GB of unified memory, and why AI data centres buy memory by the truckload.

AI chips use a special stacked memory called HBM (high-bandwidth memory). It is more complex to make than the memory in a phone, so every HBM chip made means less factory capacity for other types. That is one way AI demand pushes up the price of ordinary memory too.

How much memory does an AI model need?

Here is a rule of thumb you can use today. Memory needed equals the number of parameters times the bytes used for each one.

Memory (GB) ≈ parameters (billions) × bytes per parameter

Bytes per parameter depends on precision: 2 bytes at 16-bit, 1 byte at 8-bit and 0.5 byte at 4-bit. Lower precision (called quantization) shrinks the model.

A 7 billion parameter model:

16-bit: 7 × 2 = 14 GB

8-bit: 7 × 1 = 7 GB

4-bit: 7 × 0.5 = 3.5 GB

Add roughly 20% for working space (an assumed figure), so the 4-bit version needs about 4.2 GB.

16-bit full precision 14 GB 8-bit half the size 7 GB 4-bit quarter the size 3.5 GB
Memory for a 7 billion parameter model at three precisions. Lower precision means a smaller model that fits in a cheaper device.

A 70 billion parameter model at 4-bit:

70 × 0.5 = 35 GB, plus overhead of about 42 GB

That fits inside a 128 GB AI laptop, but not inside a phone with 12 GB.

This is why one device can run a small assistant locally and another can't. It is a simple memory sum.

Memory speed: bandwidth

Memory also has to be fast. Bandwidth tells you how many gigabytes it can move each second.

Bandwidth (GB/s) = bus width (bits) ÷ 8 × transfer rate (MT/s) ÷ 1000

A 128-bit memory bus at 6,400 MT/s:

128 ÷ 8 = 16 bytes per transfer

16 × 6,400 = 102,400 MB/s, about 102 GB/s

Chips with wider buses and stacked memory like HBM reach many times that.

What does this mean when you buy a phone or laptop?

Common mistakes

Practice problems

Try each one before you open the answer.

1. How much memory does a 13 billion parameter model need at 8-bit precision (before overhead)?

13 × 1 = 13 GB.

2. How much does a 30 billion parameter model need at 4-bit?

30 × 0.5 = 15 GB.

3. What is the bandwidth of a 64-bit bus at 5,600 MT/s?

64 ÷ 8 = 8 bytes. 8 × 5,600 = 44,800 MB/s, about 44.8 GB/s.

Trending terms explained

Frequently asked questions

Why are RAM prices going up?

Demand from AI data centres and AI devices is competing with phone, PC and tablet makers for a limited supply of memory chips, and new factories take years to build.

What is the difference between RAM and storage?

RAM is fast, short-term working memory that clears when the power goes off. Storage is slower, long-term memory that keeps your files.

How much RAM do I need for local AI?

Multiply the model's billions of parameters by the bytes per parameter, add about 20% overhead, and keep some memory free for the system. A 7 billion parameter model at 4-bit needs about 4 to 5 GB.

What is HBM?

High-bandwidth memory is stacked memory placed beside an AI chip, giving it far higher bandwidth than normal memory.

Sources and further reading

Market details are based on tech news roundups from early October 2026, including Notebookcheck and Tech Startups. Prices and products change often. The sums on this page use example figures, so replace them with your own device and model numbers.

Convert and compare numbers on the way, or check how power works in your devices.

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