HP Prodesk 400 G6 mini PC Upgrade

[Kelund]

For those considering buying and upgrading an HP Prodesk 400 G6.

I bought the model as seen without any warranty through a man who had bought several from a bankruptcy estate.

I checked on site that it would start and there were no visual defects before purchasing.

At home, it started installing Windows 10 Pro.

It wouldn't proceed to Windows 11. It turned out that TPM was not enabled in the BIOS but only displayed as TPM - could be seen in Windows. After enabling it, it automatically updated to W11 Pro.

I noticed that every time the power was unplugged, it took longer to start up. I measured the RTC battery (BIOS battery) and it was below 3.0 volts. It was replaced with a new one, which helped immediately.

I noticed that the Wi-Fi signal was weak, and I measured poor downloads - My Wi-Fi router is in another room 8-10 meters away and on another floor.

Therefore, I decided to install an external antenna.

I chose to buy:

Antenna cable:Delock Antenna Cable RP-SMA jack to MHF4 plug (IPEX), Item number 88815

Antenna: Delock RP-SMA Antenna WLAN 2 dBi, Item number 88395

I didn't want a large antenna, but other models can certainly be found.

Note that the important thing here is the MHF4 in the description.

The length of the cable can be just 15 cm, but I couldn't find that. The mentioned model is 20 cm but can be arranged to be hidden on the side.

I had a WIFI Intel AX210 card lying around, so I chose to install it at the same time.

It is recommended to use plastic tools for the installation and make sure there is no power connected.

Note: It is a good idea to disable "Quick Start" in BIOS. This forces the BIOS to look for changes when it starts up.

The installation process is simple. Remove the small round plate on the back with a screwdriver. Gently tip back and forth until it loosens. Remove the small connectors on the existing Wi-Fi card, unscrew the Wi-Fi card, lift it up, and pull away.

The external antenna should function as the main antenna. Find the word main on the Wi-Fi card and connect the connector to the cable.

Note: It is easiest to connect the connector to the Wi-Fi card before installing the antenna, as they are very small and hard to attach. Mount the cable to the PC case and connect the last antenna cable to the Wi-Fi card and place the card in the holder and screw it down.

Make sure the cables are free of the SSD NVMe. Hold the connectors with a finger while gently twisting them. The excess antenna cable was taped to the connector and tucked away - found some space around the speaker where it is not in the way.

Turn on the PC and let Windows find and install the card.

For me, this meant an improvement of 8-10 times downloads. It might not mean much in an office environment where coverage is better.

TIP: I have installed Intel support assistant. It ensures that the Wi-Fi card software is updated, and there are frequent updates.

After Windows 11 Pro was installed, I could see that a lot of RAM was being used. It works fine with the 8 GB of RAM, but I decided to buy 2 identical x 8 GB RAM to improve overall performance. I chose G.Skill SO-DIM, DDR4-3200 8GB x 2, F43200C22D-16GRS.

 The installation is very easy. Lift the fan, remove the current RAM stick, and place the new RAM sticks in. Lift the fan back into place and turn on the PC. The first startup might take a bit longer, but it will find new RAM.

NOTE: Neither the CPU nor the motherboard supports 3200MHz, but 2667MHz. So don't expect 3200MHz, it will set the speed to default.

In my search for possible Flex cards for the model, I came across: Flex Card:

HP Type-C USB 3.1 Gen2 Port Flex IO v2, 13L59AA

The card supports USB Power Delivery according to the information I could find online.

The installation was easy. Remove the backplate on the back with a screwdriver. Use as little force as possible to loosen the backplate. Insert the Flex card and screw in the two included screws. Turn on the PC and Windows will find the new card by itself.

I can now use my docking station and only need to connect the USB-C cable to get power, display, keyboard, mouse, and webcam to work.

Note: It is important that the adapter delivers enough watts via the docking station to avoid problems.

Additionally, I gave the CPU a new thermal paste and blew away old dust, as well as cleaning the outer surfaces.

I hope someone can benefit from my information.