PCI vs PCIe: Differences and Comprehensive Comparisons (Latest Updates)

PCI vs PCIe: What are the differences?

In a computer, data exchange happens through buses connecting devices like graphic cards, hard drives, SSDs, WiFi, and Ethernet to the processor subsystem. Peripheral Component Interconnect (PCI), Peripheral Component Interconnect eXtended (PCI-X), and Accelerated Graphics Port (AGP) were older bus protocols, now replaced by the current standard, PCI Express (PCIe). Why the PCIe can replace the PCI? What’s the differences?

PCI vs PCI Express in data transfer speed

One of the primary reasons for the transition from PCI to PCIe is the substantial increase in data transfer speed. While PCI has a data rate of 133MB/s, PCIe offers significantly higher speeds, with a data rate of up to 16GB/s for a 16-lane slot. PCIe speed varies based on lanes and versions, as illustrated in the Wikipedia PCIe performance diagram. This enhanced speed is important for modern computing needs, especially with resource-intensive applications and high-performance components.

PCI vs. PCIe comparison in interface

PCI uses a parallel interface, where individual buses are dedicated to each connected device. In contrast, PCIe employs a serial interface, sharing a common set of lanes for data transmission. The serial nature of PCIe contributes to its higher efficiency and faster data transfer rates compared to the parallel structure of PCI.

In summary, the shift from PCI to PCIe in professional computing is motivated by the demand for faster data transfer, the efficiency of a serial interface, streamlined motherboard design, and the direct connectivity to the CPU.

Currently, PCI, PCI-X, and PCIe cards coexist in the market. If you concern about PCI vs PCIe compatibility

However, as PCIe network cards provide compatibility with modern operating systems and faster speeds, computer hardware designers and manufacturers are increasingly incorporating PCIe into their latest products. The gradual replacement of PCI/PCI-X by PCIe is inevitable, and PCI-based cards are expected to become obsolete soon.

For M.2 PCIe SSDs:

If the graphics card uses PCIe 3.0 X8 lanes, and other PCIe 3.0 X4 ports connect NVMe SSDs, each SSD enjoys 4 GB/s throughput exclusively.

If the graphics card uses PCIe 3.0 X16 lanes, and the M.2 PCIe SSD shares 24 PCIe lanes with other devices, SSD speed is limited by DMI 3.0. Thunderbolt 3, M.2, and U.2 interfaces can't exceed PCIeX4 bandwidth. Despite sharing throughput, PCIe SSDs are faster than SATA SSDs, and DMI 3.0 throughput suffices as additional Southbridge devices usually don't operate simultaneously.

Migrate your Windows to a PCIe SSD

Once you understand the difference between PCIe and PCI, you might prefer using PCIe products. If your computer has a PCI-E interface using a Windows computer, you can definitely experience the high-speed benefits of PCIe.

To get this done, it's best to use AOMEI Partition Assistant Professional, a complete computer management tool. It lets you move just the operating system or transfer all your data, like files and programs, based on what you need. Now, let's go through the steps in detail.

▌Migrate OS only:

Step 1. Start the installed AOMEI Partition Assistant Professional. Choose Clone > Migrate OS from the top section, and take a look at the introduction in the next window.

Step 2. Choose the SSD as the destination disk. If there are partitions on this disk, mark the option "I want to delete all partitions on this disk 2 to migrate system to the disk."

Step 3. Resize the system partition on the target disk if you need to.

Step 4. Please remember this note as it may be useful later on.

Step 5.  Return to the main interface, and then click on Apply to carry out the pending operations.

▌Transfer all the data:

Step 1.Install and launch AOMEI Partition Assistant, click the "Clone" main tab and select "Clone Disk". (You can also right-click the Disk you want to clone and select the "Clone Disk" tool to run disk clone.)

Step 2. Choose the hard disk that you need to clone as the source disk and click "Next".

Step 3. Select the destination disk to put the data of the source disk on, and then click "Next".

Step 4. Then, you will enter the Confirm interface where you can check the source and destination disk. After all is set, you can click the "Confirm" button to continue.

In lower left corner of the window, you can click the "Settings" button to adjust the partition size on the destination disk. There are three options for you:

• Clone without resizing partitions: all partitions will be cloned to the target disk as the original partition size. It is available when the target disk is larger than the source disk. If it is smaller, this option will be grayed out.
• Fit partitions to entire disk: all partitions will be cloned to the target disk and take up its full capacity according to the original partition size proportion.
• Edit partitions on this disk: you can change every partition size on the target disk as you need.

After finishing the adjustment, please click "Save".

Notes:

• You can tick "4k alignment" to improve the reading and writing speed of SSD if the selected destination disk is an SSD storage.
• All data on this selected destination disk will be wiped out after you save the operation to physical disk. If there is important data on the destination drive, please make a backup in advance.
• If you clone to a smaller SSD, the first option is grayed out. If you select Sector-by-Sector Clone, it is unable to adjust the size on the destination disk.

Step 5. You can preview the disk cloning operating by viewing the "Pending Operations". To commit the "Pending Operations", please click "Apply" and "Proceed".

Step 6. The cloning process will start and you can check the cloning process.

Summary

If you are curious about PCI vs PCIe, this passage highlights distinctions in their slot, speed, compatibility, and more. If you wish to enjoy the benefits of a PCIe SSD, you can use AOMEI Partition Assistant to transfer the data based on your needs.

Afterward, it is advisable to use the software for further management. For example, you can easily merge/resize/delete/move partitions, extend drive space, rebuild corrupted MBR, convert between GPT/MBR, and so on. For Windows Server users, please choose the AOMEI Partition Assistant Server edition.