Detailed explanation of applied tweaks

This guide will give you a detailed explanation of each applied tweak in the script.

Contents

1. GRUB
2. Power management
3. Audio enhancement

GRUB

The first tweak applied to the ISO is the list of boot options at in the GRUB entry. The added options are the following:

acpi_rev_override=1 acpi_osi=Linux scsi_mod.use_blk_mq=1 vga=0 rdblacklist=nouveau nouveau.blacklist=1 nouveau.modeset=0 nouveau.runpm=0 mem_sleep_default=deep
pti=off spectre_v2=off l1tf=off nospec_store_bypass_disable no_stf_barrier

• acpi_rev_override=1 acpi_osi=Linux These two are pretty common in the Linux world, and they simply make some changes in the way ACPI works (because many laptops comes with non-standard ACPI).
• scsi_mod.use_blk_mq=1 This is a simple tweak to force the Linux kernel using block multi-queue mode, allowing a better usage of the NVME drive.
• nouveau.modeset=0 nouveau.runpm=0 These the more important, as they allow to prevent nouveau (the open source nVidia driver) from managing the nVidia card.
• mem_sleep_default=deep This fixes the resume problems with the nVidia card. The other options which disable SPECTRE/Meltdown patches for additional performance, though they're completely optional. The pre-built ISO doesn't disable them.

Power management

For lowering power consumption, TLP gets automatically installed, together with powertop (a tool which lets you analyze in detail the various consumption of the system parts). Other than that, few experimental options for the Intel card are activated:

options i915 enable_fbc=1 enable_guc=3 disable_power_well=0 fastboot=1

• enable_fbc=1 turns on framebuffer compression, that can reduce power consumption while reducing memory bandwidth needed for screen refreshes.
• enable_guc=3 just force loading the GuC/HuC firmware, enabling some video features.
• disable_power_well=0 Try to disable possible power wells
• fastboot=1 Just enable faster display boot Being experimental, they can have some impact on smoothness or stability, but they can easily be turned off as covered by the troubleshooting page you can find in the wiki. The

options dell-smm-hwmon restricted=0 force=1

line loads dell-smm-hwmon kernel module, which allow to check thermal-related things

Audio

The XPS is capable of reproducing high quality audio, so I enabled it by shipping a tweaked configuration of PulseAudio, following this guide: https://medium.com/@gamunu/enable-high-quality-audio-on-linux-6f16f3fe7e1f