In a previous project, I used an old laptop motherboard as a central piece for my all in one touch computer.  Last week I received a new CPU that I will install in it to refresh it a little bit.Because the laptop is from 2007, the components are a little bit dated and the system (Windows 8) is a little bit slow. Because the technology is a bit behind, I managed to score a top of the line CPU on Aliexpress for 25$, going from a Core 2 T5250 (1.5Ghz) to a Core 2 T9300 (2.5Ghz). Here’s the short project log on how I did it.

Find the perfect CPU

Changing a CPU on a laptop motherboard is more challenging than on a desktop computer. This is because laptop manufacturers don’t always add support for all CPUs into the motherboard software, the BIOS.

The best way to find a CPU compatible with your machine is then to try and find which CPU were available on your laptop, which (should) guarantee you to have a functional CPU once installed. Of course the normal rules applies – So to get a CPU compatible with your machine:

•  Same socket on the motherboard (the physical connection, the number of pins needs to match)
•  Same chipset (the motherboard “brain”)
•  CPU available for your laptop.

My old laptop was a Asus Z99, which have the same motherboard as a Asus A8Sc (important to know, there can be variants in names but using the same hardware). I first retrieved information from my CPU using the PassMark table, and found out which CPU were compatible with my chipset and socket. Once I got a couple of CPUs that could work I started searching for their reference with the laptop reference on google, something like “asus a8sc core 2 T9300”, which helped me confirm that the CPU was compatible.

Finally, I went on Aliexpress, made sure the CPU was not too expensive (25$) and bought it. Two weeks ago it arrived in the mail

Installing the new CPU

The last step is just to screw back the cooling module and turn on the computer.

BIOS update

So, when I turned on the computer, nothing happened. No bip, no image no nothing. This is because I had an older version of the BIOS that didn’t handle the newer kind of CPU I bought. The solution was to update the BIOS to a newer version.

Here’s the procedure:

• Get Asus AFLASH2 software (BIOS update software), you can get it from Asus support website on the page of your laptop
• Get the binary file containing the BIOS for your laptop
• Download and install FreeDOS on a USB key (I followed instructions from this website)
• Copy over aflash.exe and the bios file (unzipped) in the newly created USB key.
• Boot from this key and execute the aflash.exe program
• Follow the instructions on screen to update the BIOS
  • Something like “LOAD BIOS FILE”
  • Then “PROGRAM FLASH ROM”

It takes a couple of minutes then tells you it’s done:

Restart the computer and Tada! the new CPU is now installed and fully functionnal. It is making a big difference performance wise on my computer. Money well spent 🙂