(UEFI) Dell XPS 15z L511z modded BIOS - and HOWTO

[kasar]

ok, I have good news and bad news.

good news is that it worked! ^^





the bad news is that I am just able of modify the language feature.

I cant move over/select the advanced settings menu.

that text over the advanced menu is quite suspicius.

did you found similar problem while unlocking your 15z menus?

edit: I noticed there is another 00 29 02 29 02 0A 82 45 8A hex values in the file, I will modify also that one, I will update the post with the results

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ok, modifiing also the another string was the final fix!

this is crazy!

loving the extra menus! I can even disable the HT feature!













so after modify those 2 values, I finally got the l502x bios unlocked!

thanks a bunch for the info man, you are my hero today

[fuwu1245]

Wow～
It is really an exciting news~
We have an unlocked BIOS~

[jkbuha]

I've updated the first post with the modded 15z BIOS, together with a brief HOWTO.

@kasar - glad to be of help my friend, you've been involved since the very beginning - hard work pays off in the end and I'm happy to see you're also really excited by the discovery

Our journey is not over yet. Now we need to do the following:

1) Check to see if really all menus have been decoded
2) Start to understand what all these crazy options mean
3) Construct a generic howto as to patch all Dell BIOSes
4) IMPORTANTLY: ALSO DISCOVER A WORKING RECOVERY METHOD FOR DELL UEFI BIOSES!

But importantly I need to thank my good friend Mikhail who has helped me tremendously in the field of IFR decoding. Without him we wouldnt be here today!

[TimeWalker]

Wow, guys, wow! This is what I wake up to see!
Congrats jkbuha on finally beating this thing with a stick lol
I see tons of options that have no meaning for me, but the ones I'm most interested in are UEFI boot and PTID (this is the monitoring device).
Will try searching this HEX sequence in my Vostro's UEFI BIOS and report back.. even though I'm kind of skeptical about flashing it right away because machines are kind of of different line-up.

I'm currently staying on A04 BIOS with my Vostro 3450 since this is the most stable for OSX installation and has no troubles with sleep feature. Will modify this one first to see what changes it brings.
I've located the PlatformSetupAdvancedDxe.efi module, it has a GUID of CFEF94C4-4167-466A-8893-8779459DFA86_1_1071 and is 279 KB in size.
Looking for 00 29 02 29 02 0A 82 45 8A 00 bring this ...
First occurrence is here:
Second occurrence is here:

Please confirm that this is the part that I need to be replacing values in: http://pastie.org/4859643
And here is the entire i386 disassembly of the mentioned module: http://dl.dropbox.com/u/2573233/ADVANCED.asm

[HairyCube]

hey TimeWalker, I actually managed to unlock hidden options in Vostro 3450 BIOS using the guide by jkbuha. I flashed it and it seems to be working fine. I got access to lots of options, and while most of them work, Switchable Graphics options don't seem to do anything.
Anyway, here's the BIOS image for Vostro 3450 (version A11), advanced tab fully unlocked: https://dl.dropbox.com/u/91178815/BIOS1.WPH
Sorry I haven't touched A04 yet, but I suggest you take a look at it anyway.
And thanks jkbuha for an awesome breakthrough!!

[TimeWalker]

Ok, thanks for the heads up! I just patched and flashed A04. I can confirm the trick worked flawlessly.
Now to figure what most of these options mean, like jkbuha said
Huge props for unlocking this nonsense!

P.S. I'm most definitely positive about about UEFI boot (enabled UEFI and disabled Legacy for the sakes of testing). Because this comes up when I try to run Repair on my Windows 7 legacy installation: http://puu.sh/19EPE
P.S.S. Yeah, it most definitely works now, as creating a flashdrive with EFI/BOOT/bootx64.efi results in Windows Boot Manager shouting that it can't boot the OS (no sh*t, Sherlock). Prior to unlocking it would just say 'No Operating System Found'

Also, HairyCube (this makes me giggle every time I read it as I try to imagine how it would actually look IRL LOL ) try rolling back to A04.
There have been some changes in later BIOS versions in regards to Switchable Graphics operation modes as well as USB3.0 stuff. For me USB3.0 changes have a negative impact, so might as well try what A04 brings you. Here's the rom I had patched (includes MSR unlock as well): http://dl.dropbox.com/u/2573233/V3450_ULCK_A04.zip

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Disabling PTID seems to give the CPU fan it's own 'space' ... as it is no longer forced by DTS to operate in just the 2-way mode like previously: 0RPM -> 4k RPM without any steps in-between. Now it always spins quietly at around 1200rpm and only increases the RPMs when the temps climb above 65C (gaming, video etc). I prefer this behavior rather than occasional 'JET' moments for no apparent reason.

[HairyCube]

Hey TimeWalker, thanks for the suggestion and the BIOS image. Unfortunately it seems that Switchable Graphics and Primary Display Device options are not linked to do anything. No matter what option I set, when I boot Windows, it is always in "automatic" switching with A04 and "automatic/manual" on A11. Setting primary display device to PEG or Switchable Graphics to dGPU or Disabled doesn't affect anything at all. This is so disappointing

P.S. Sorry about offtopic, perhaps we need to make a new thread about Vostro 3450?

[TimeWalker]

As pointed out by the user HairyCube (huge props!) try looking for 00 20 00 29 02 0A 82 45 8A 00
Swap the last byte to 01 - this will unlock Thermal Configuration tab in Advanced Menus.


This is only a part of it. The values TC1 TC2 and TSP are written into registers and are involved in ACPI "passive cooling formula":

Later on passed on to DTS via ThermalZones:

Code:

           Method (_TC1, 0, Serialized)
           {
               Return (TC1V)
           }
           Method (_TC2, 0, Serialized)
           {
               Return (TC2V)
           }
           Method (_TSP, 0, Serialized)
           {
               Return (TSPV)
           }

I was able to crank up the values for the low level fan kick-in, with disabled PTID it runs much quieter now .. also with enabled PTID its as silent as dead, of course if you are doing some basic office stuff, like word processing etc.

[jkbuha]

haha nice work TimeWalker! I tried it and it unlocked the thermal settings. A quick search for the offset 29 02 0A 82 45 8A 00 throughout the file shows that now all are set to 01 (apart from the change language to French, but for me it's not really an issue).

Where is the PTID option? There's a lot of thermal settings and I'm a bit reticent to change them at the moment.
The combination of Fast Strings + changing memory to 1600 seems to have increased speed slightly, geekbench ~3% better.

Any other killer combo settings to enable/disable?

I've just looked through the strings file, and I've just realised that the 'Overclocking Performance Menu' is still hidden, even though it is present in the bios file. Looks like some more tweaking is necessary...

[Florin9doi]

1) Dump your AdvancedSetup.efi module (IDA, objdump etc) and parse it through the IFR specification provided by UEFI

can you explain this step?