Introduction
Hi Everyone.
Recently I got Asus E200H laptop, which I would like to use as a portable computer to work with a high-precision equipment.
In the figure below we can see the parameters of the laptop dumped with the CPU-Z utility.
The device is equipped with 4-core processor from Intel with a frequency of 1680 MHz and 4 GB of RAM, i.e. it is comparable to Raspberry PI by the characteristics, but it is placed in a netbook housing with a screen and keyboard.
This netbook is equipped with Windows 10 by default. However, there is one interesting point: the size of the drive is 32 GB. This amount is enough to install Windows 10. But as soon as the computer connects to the Internet, the upgrade procedure occurs, which often occupies all of 32 GB. As a consequence, OS completely hangs, it can neither update nor roll back. As a result, the laptop is not operational.
I tried to install Windows 7 with disabled updates. If the driver package for USB3 and SSD is integrated into the OS image in advance, the OS is successfully installed. However, it is crashed during the laptop startup.
For this reason, I have installed Linux Mint. If we list the drives, we will see the following image:
zhksb@zhksb-laptop:~$ df -h
Filesystem Size Used Avail Use% Mounted on
tmpfs 381M 1,8M 379M 1% /run
/dev/mmcblk1p2 29G 12G 15G 45% /
tmpfs 1,9G 0 1,9G 0% /dev/shm
tmpfs 5,0M 4,0K 5,0M 1% /run/lock
/dev/mmcblk1p1 511M 6,1M 505M 2% /boot/efi
tmpfs 381M 112K 381M 1% /run/user/1000
As we can see, even using Mint with a lightweight Xfce desktop, it requires minimum of 12 GB of space, which is 45% of the available capacity of drive.
If we try to check the speed of the drive, we will see the following results:
zhksb@zhksb-laptop:~$ sudo hdparm -Tt /dev/mmcblk1p2
/dev/mmcblk1p2:
Timing cached reads: 2624 MB in 1.99 seconds = 1316.06 MB/sec
Timing buffered disk reads: 428 MB in 3.01 seconds = 142.42 MB/sec
In general, I didn't want to throw the device away. I decided to make some experiments with it and after to share the results at Habr. Thus, the purpose of this article is to replace the default drive with a more capacious one and to test the upgraded laptop.
Experimental part
The first thing we need to do is to find out what drive is installed by default. For this, I carefully disassembled the netbook with a plastic card and began searching for a drive.
On the back side of the motherboard the following candidate was found. I removed the label and found a chip model:
This is a 32 GB KLMBG2JENB chip with eMMC 5.1 standard from Samsung. There is a datasheet for this chip. The interesting for us piece of information from datasheet is provided in the table below.
Capacities | eMMC Part ID | Power System | Package size | Pin Configuration |
16 GB | KLMAG1JENB-B041 | Interface power: Memory power: | 11.5mm x 13mm x 0.8mm | 153FBGA |
32 GB | KLMBG2JENB-B041 | 11.5mm x 13mm x 1.0mm | ||
64 GB | KLMCG4JENB-B041 | 11.5mm x 13mm x 1.0mm | ||
128 GB | KLMDG8JENB-B041 | 11.5mm x 13mm x 1.2mm |
As we can see, there are chips with capacity up to 128 GB in the series. The only thing they differ is the height of the chip case, which is in our case uncritical.
I tried to buy a 128 GB chip, but failed to do it. At the same time I came across similar chips from Kingston and it was possible to purchase them. I found the datasheet for them, the outlines are presented below.
Product Part Number | NAND Density | Package | Operating voltage |
EMMC64G-TY29-5B111 | 64GB | FBGA153 | VCC=3.3V, |
EMMC128-TY29-5B111 | 128GB | ||
EMMC256-TY29-5B111 | 256GB |
I compared the type of the case and the pinout using datasheets. We can see them in the figure below.
It is turned out that the pinout is the same. Despite the huge costs of about 50 Euros, I decided to risk for the experiment and ordered 256 GB chip from an American supplier.
The chip came in a huge vacuum-sealed anti-static package. After unboxing, it got one small chip.
The laptop board has a sufficient heat capacitance, so we need an additional heating from the bottom. I used a lab heater with a temperature limit of 150 degrees and a separate thermocouple. I set the bottom heating temperature at 110 degrees. Before the chip resoldering, I checked the whole system to ensure that there was no overheating or damage to the test PCB under the specified conditions. The test was successful.
The netbook board was extracted and put on the heater. Before heating the stickers were peeled off to avoid burning. The circuit board was wrapped with a heat-resistant tape to prevent the SMD components fly away with the flow of air from the heat gun. After warming the heater up to 100 degrees by the thermocouple, I added the flux for desoldering along the contour of IC and started the heating of the old chip with a desoldering gun at 380 degrees and with a small flow of air.
The chip did not give up in for a long time, so I had to raise the temperature up to 400 degrees. As a result, we have an old chip, and all of the pins at PCB, fortunately, remained in place. I added a new flux portion and gently removed the remaining solder from the board using a copper braiding. The residue of the flux after soldering was cleaned with a soaked with the flux remover cotton wool.
As a result, we have perfectly prepared socket for new IC soldering. I added a new flux portion, put the chip taking into account the IC key and warmed the board on the heater up to 100 degrees. Next, I soldered the chip at 400 degrees for 10 minutes. The temperature at the top was about 230 degrees. I didn’t see when the chip was soldered, I just waited for the board to cool down and made sure the chip was soldered.
After the board was completely cool, I removed the tape and washed the board from the remained flux.
At the end, I put the board back into a netbook.
Results
In this step we try to launch the laptop. It successfully turned on and immediately entered the BIOS, i.e. nothing is corrupted.
After, I tried to load Linux Mint using pen stick and checked the disk status.
zhksb@zhksb-laptop:~$ df -h
Filesystem Size Used Avail Use% Mounted on
tmpfs 381M 1,8M 379M 1% /run
/dev/mmcblk1p2 229G 11G 206G 5% /
tmpfs 1,9G 0 1,9G 0% /dev/shm
tmpfs 5,0M 4,0K 5,0M 1% /run/lock
/dev/mmcblk1p1 511M 6,1M 505M 2% /boot/efi
tmpfs 381M 112K 381M 1% /run/user/1000
We see that instead of 29 GB there are 229 GB now, i.e. the upgrade was successful! Later I installed Mint on the drive and tested the speed of reading.
zhksb@zhksb-laptop:~$ sudo hdparm -Tt /dev/mmcblk1p2
/dev/mmcblk1p2:
Timing cached reads: 2616 MB in 1.99 seconds = 1311.63 MB/sec
Timing buffered disk reads: 428 MB in 3.00 seconds = 142.60 MB/sec
It was almost the same.
Conclusions
In summary, it is possible to upgrade eMMC chips without any problems. However, this netbook uses UEFI, so the disk is only used as a drive. This trick will not work for smartphones because it is necessary to create the required disk partitions and burn the boot loader. Nevertheless, I consider the results of this experiment to be important and useful.
Thank you for attention!