--- layout: wiki title: DellInspiron17-3721 updated: 2026-03-30 08:04 author: rick default: false toc: true --- ## The Problem I have got a Dell Inspiron 17 3721 laptop which does not turn-on anymore. Only a single beep error code, nothing on the screen. Beep code 1 means: "Motherboard: BIOS ROM Failure". ![dell_inspirion_beep_codes.png](attachments/dell_inspirion_beep_codes.png) Source: ## The Idea A corrupt BIOS ROM, how-to repair? The BIOS chips are SPI based EEPROMs of type SOIC8, which are most likely became corrupted somehow. [Looking around at bios-fix.com](https://bios-fix.com/index.php?threads/dell-inspiron-3721-bios-schematic-boardview.38189/) there are two chips which needs to be flashed. Digging through my pile of hardware a have a buspirate v3 which I could use to re-program the BIOS chips. - I need to be able to access the chips. The [Owner manual](https://downloads.dell.com/Manuals/all-products/esuprt_laptop/esuprt_inspiron_laptop/inspiron-17-3721_Owner%27s%20Manual_en-us.pdf) is a good source for opening the laptop. - De-soldering the BIOS. - A SOIC8 test clip is required with good quality cables. [The guide at dangerousprototypes.com](http://www.dangerousprototypes.com/docs/Flashing_a_BIOS_chip_with_Bus_Pirate#SOIC8_test_clip) will help me make one. - Flashrom software on Windows using MSYS2, using [build from source guide at flashrom.org](https://www.flashrom.org/dev_guide/building_from_source.html#windows). - I need up2date firmware on the buspirate to program the chip, using: - [https://maidavale.org/blog/flashing-the-bus-pirate/](https://maidavale.org/blog/flashing-the-bus-pirate/) - [https://dangerousprototypes.com/docs/Bus_Pirate#Firmware_upgrades](https://dangerousprototypes.com/docs/Bus_Pirate#Firmware_upgrades) - tooling found at [https://github.com/therealdreg/buzzpirat](https://github.com/therealdreg/buzzpirat) - Next I need to flash the chips, using a little inspiration from: - [https://www.nsideattacklogic.de/en/dumping-spi-flash-memory-of-embedded-devices-2/](https://www.nsideattacklogic.de/en/dumping-spi-flash-memory-of-embedded-devices-2/) - [https://winraid.level1techs.com/t/guide-flash-bios-with-ch341a-programmer/32948/56](https://winraid.level1techs.com/t/guide-flash-bios-with-ch341a-programmer/32948/56) - [http://www.dangerousprototypes.com/docs/Flashing_a_BIOS_chip_with_Bus_Pirate](http://www.dangerousprototypes.com/docs/Flashing_a_BIOS_chip_with_Bus_Pirate) - [https://kean.com.au/oshw/WR703N/teardown/](https://kean.com.au/oshw/WR703N/teardown/) ## The Implementation ### BIOS ROM images First challenge find the BIOS ROMs which I could flash on the chips. I have tried to extract them from the official BIOS download page [Dell Inspiron 3721 System BIOS - A14, 3721A14.exe](https://www.dell.com/support/home/en-us/drivers/driversdetails?driverid=70h05) how-ever I was not able to extract the required files. I found at older version at [halabtech.com - Dell Inspiron 17 3721 A12 Bios Files.zip](https://support.halabtech.com/index.php?a=downloads&b=file&id=775322) which I will use and later update to the A14 version. ### Get both BIOS chips Dis-assemble laptop using Owner Manual and de-solder BIOS chips located at UH2 (EN25QH16) and UH6 (EN25Q32B). ![UH2.jpg](attachments/UH2.jpg{style="max-width:120px"}) ![UH2.jpg](attachments/UH2.jpg{style="max-width:120px"}) ### Compiling flashrom for Windows ``` # Install using https://www.msys2.org and load the UCRT64 environment https://www.msys2.org/docs/environments/ $ pacman -Syu $ pacman -Sy mingw-w64-ucrt-x86_64-gcc mingw-w64-ucrt-x86_64-meson mingw-w64-ucrt-x86_64-ninja mingw-w64-ucrt-x86_64-pkg-config mingw-w64-ucrt-x86_64-python-sphinx mingw-w64-ucrt-x86_64-cmocka mingw-w64-ucrt-x86_64-libusb mingw-w64-ucrt-x86_64-libftdi mingw-w64-ucrt-x86_64-libjaylink $ pacman -S base-devel binutils git pactoys cc libusb meson pkg-config # $ git clone https://github.com/flashrom/flashrom.git 10 git clone https://github.com/flashrom/flashrom.git 11 cd flashrom/ 13 meson setup builddir 14 meson compile -C builddir ``` ### Updating BusPirate ``` $ git clone https://github.com/therealdreg/buzzpirat.git $ cd buzzpirat/bin # Ensure jumper between PGD and PGC before powering-on BusPirate $ ./buzzloader/pirate-loader.exe --dev=COM4 --hex=./oldfirm/BPv3-bootloader-upgrade-v4xtov4.5_Sep-2020_USBEprom.hex --verbose # 'Error updating firmware :(' is expected and 'normal' behaviour. $ ./buzzloader/pirate-loader.exe --dev=COM4 --hex=./stablefirm/bpv3comp/BPCOMPBZ-firmware-v7.1.12.hex # 'Error updating firmware :(' is expected and 'normal' behaviour. # FYI: plink.exe is part of Putty CLI, download at https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html $ plink.exe -serial COM4 -sercfg 115200,8,2,1,n # Press 'i' + 'Enter' to check for new firmware version ``` ### Flashing de-soldered chips ``` # In MYS2 UCRT64 environment $ cd flashrom # Connect EN25QH16 chip to SOIC8 test-clip $ ./builddir/flashrom.exe --programmer buspirate_spi:dev=COM4 -w 2MB\ \ EC\ \ .BIN --progress # Connect EN25Q32 chip to SOIC8 test-clip $ ./builddir/flashrom.exe --programmer buspirate_spi:dev=COM4 -w 4MB\ BIOS.BIN --progress ``` ## The Result After re-assembly and soldering both UH2 and UH6 back in place, the laptop booted with 5 error codes, some progress ;-). After replacing the CMOS battery and fixing the terminals (both needed some bending back in place). I give it some more reboots and voila it was working again :-). Another laptop saved from the junkyard and some interesting stuff learned during the process.