# CoreBook X (2021, i5-8259U) BIOS/UEFI Resources **URL:** \ **Category:** CoreBook X\ **Created:** [November 30, 2022, 6:29pm UTC](https://forum.chuwi.com/t/corebook-x-2021-i5-8259u-bios-uefi-resources/36442 "2022-11-30T18:29:17Z")\ **Posts on this page:** 1\ **Showing post:** 3
**Author:** ![fat\_bird](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.chuwi.com/fat_bird/32/6982_2.png) [@fat\_bird](https://forum.chuwi.com/u/fat_bird)\ **Post date:** [December 21, 2022, 9:15pm UTC](https://forum.chuwi.com/t/corebook-x-2021-i5-8259u-bios-uefi-resources/36442/3 "2022-12-21T21:15:14Z")
No problem. I’ve answered what I know about your particular situation in the other thread where you posted the details: > [@Need BIOS update for Corebook x](https://forum.chuwi.com/t/need-bios-update-for-corebook-x/35840/6): > > For the record, you have the i5-7267U, which I think is the 2020 model. The 2021 model is the one with the i5-8529U. How the keyboard works is determined by the keyboard controller (KBC), a part of the embedded controller (EC). You have version CH-EC-V1.1.4 of the EC firmware. Seems there is a newer version CH-EC-V1.1.7 around, along with a matching BIOS version JXX-14-WU133SR200-V1.1.7. There exists also another version CH-EC-V1.8.0, which might be an even more recent update. Or it might be f… I can only talk about the i5-8529U model, which is what I have. It looks very much the same but in terms of firmware it’s completely different. Some of the following might not apply to the other variants (including yours): - Firmware (BIOS) can be easily read and flashed with Intel FPTW64. There is no protection of any kind. Since FPTW64 works and we don’t have any OEM images, I didn’t test AMI’s AFUWIN64 but it should probably work as well. - Flash chip is XMC XM25QH128C. It’s a bit uncommon but supported by Flashrom in the recent versions. Support is experimental (untested). - I was able to probe and read this chip using Flashrom with a CH341A hardware programmer. I didn’t try erasing or writing. - There are 3 BIOS versions I’ve been able to confirm the existence of: - BIOS version 1.0.8 has EC version V1.04. With the earlier 1.0.5, the EC version string was “090200.1717” (or maybe “902.001.717” – not sure, since I only saw it on a screenshot). - I could not obtain any BIOS dumps shared by other people. - The laptop I got already came with BIOS 1.0.8 / EC 1.04, which seems to be the latest version. - Since everything is already unlocked, I just changed the boot logo and called it a day. - I’ve been experimenting with memory overclocking settings but have been unable to make it run at anything past the default 2400 MT/s, even if the onboard 8GB memory is disabled. This seems to be a CPU/SoC limitation, since the additional memory stick I installed is DDR4-3200, so it can definitely do more. If anyone’s had any success speeding up the memory, I’d be interested to know. - Thus far, I didn’t even play with many of the other settings. But for the record, this variant does have the ability to toggle the Fn key mode: it’s under _Advanced_ → _Function Keys Mode_ in the BIOS and was set to _Standard F1-F12 Mode_ by default. --- _[View the full topic](https://forum.chuwi.com/t/corebook-x-2021-i5-8259u-bios-uefi-resources/36442)._