Why is the nominal capacity of the hard disk so much different from the actual capacity

Because computers are binary, the operating system calculates the hard disk capacity in 1024 increments, while the hard disk manufacturers use every 1000 in terms of computing capacity.

At present, the mainstream hard disk capacity is 250G, 320G, 500G, 1TB, etc., according to this operation rule, to calculate the correspondence between the labeled capacity of the commonly used hard disk and the real whole disk capacity.

Each hard drive will make a defect mapping table based on the test results, and lock these areas to prohibit access, unless you use professional tools to access these defective areas.

You actually see that the continuous space is only logically continuous, and it may not be continuous inside the hard disk, which means that the hard disk you get has actually been processed by the manufacturer.

If the partitioned cluster area (data area) is not an integer multiple of the cluster size, the sector space of less than one cluster will be left free unless it is diverted for other purposes.

The hidden partition of ordinary brand machines is also not displayed by default on the operating system, so it also takes up space. There are also certain special encrypted partitions.

Simplify the conversion formula: nominal capacity * actual capacity, how much do we take 320*? The answer is!!

In line with what the landlord said, it is more than 20g less!! Conclusion: That's right, normal!!

Now the largest 1500g hard disk, the error has exceeded 100g, reaching amazing!!

Normal very. Manufacturer capacity calculation method: 120GB 120,000MB 120,000,000KB 120,000,000,000 bytes.

Converted to operating system, 120,000,000,000 bytes 1024 117,187,500kb 1024 114,.

At the same time, in the operating system, the hard disk must also be partitioned and formatted, so that the system will also occupy some space on the hard disk and provide it for system files to use, so there will be a difference between the hard disk capacity and the nominal capacity displayed in the operating system.

Some notebooks also natively support D2D recovery technology, so there are also hidden partitions built into the hard drive, further reducing the amount of space that can be seen.

The calculation method of the merchant is different from the actual calculation method, the merchant is calculated according to 1g=1000m, and the actual should be 1g=1024m, so there will be deviations.

Not only the hard disk is like this, but the USB flash drive is also the same, and there will be deviations.

Calculation method + hidden area together, this is normal.

Calculation method problem: In a computer binary system, 1024B = 1KB, 1024KB = 1MB, 1024MB = 1GB

But with hard disk manufacturers, it's all 1000 base.

Hidden area problem: the hard disk will have a hidden fixed sector, which is used to store some hardware information, and some hard disks also have special chips to do this thing, just imagine, no matter how you format the hard disk, the computer can always read out the manufacturer of the hard disk. That's what it is.

The manufacturer's capacity algorithm is 1000MB = 1GB, 1MB = 1000KB, and 1KB = 1000B

It's much worse than the 1024 algorithm we usually use.

Because of this algorithm, there is a very famous hard disk manufacturer who has also suffered lawsuits.

The difference between 1000 carry and 1024 carry comes out after careful calculation, and you have a loss when you are divided.

Whether the independent graphics card is based on the hardware on the host computer is known, and the graphics card interface integrated on the motherboard is integrated.

The hard disk is 1000m = 1g

The computer is 1024m=1g

The algorithm is not the same.

Just look at the graphics card interface behind the host.

Use the software to check, or my computer right-click on the properties of the hardware to see the graphics card.