Dell XPS 15z (L511z) BIOS modding (UEFI booting, Nvidia GFX replacement, Advanced Menus, Native Speedstep) and more!

Hi all

Some of you may know my work from other bios modding forums - we have been busy researching on how to open the full potential of the Dell XPS laptops. After lots of hard work we have finally unlocked most, if not all, of our Dell's excellent hardware potential.

Initially I'll just be posting a few ROMs as a proof of concept. Once we get more requests - and importantly, feedback! - I'll start to add more configurable ROMs.

For now, here is the latest Dell XPS 15z A11 ROM, fully unlocked with Nvidia GPU undervolted to 0.83V/0.85V and native speedstep enabled for anyone who runs OSX.

CPU Support: All i3 series, i5 series and i7 series.

Note: I've kept the Intel vbios same as stock for now for compatibility purposes.

Get the file here: Dell XPS15z L511z BIOS A12

When I'm given more quota to upload a 2MB file to this form I'll post it here

Flash the file in windows with the following command line:
winflash.exe /BIOS /EC /SA /SV /CVAR /BBL file.WPH

With gaming the temperature drops with the new bios because the GPU is undervolted. There's a brilliant thread by captainkasar on the L502x that explains this in more depth (he's using the same mods) so if you use it more for windows and gaming I'd strongly advise you to check out his thread. There's a bug in the nvidiainspector that shows 0.98V but its actually running at 0.85V (I know because I set those limits in the BIOS GPU)

DISCLAIMER: This file is for the Dell 15z only! Even though this flash is a safe process for this hardware, there is no (known) recovery method for Dell UEFI bioses yet and so I do not take any responsibility for improper use of this file!

Respect goes out to Mikhail, captainkasar, djjonastybe, kasar, androdev and Ahmed - thank you for the great work done so far! Let's unlock all the potential of our Dell machines!

Cheers
jkbuha

 

nice work!

 

A couple questions:

Does winflash work in Windows 8?

Do you see any improved battery life in windows with the undervolted GPU?

Thanks for your work on this, I'm glad to see an active community still thriving for the 15Z!

 

Yes to both questions. At 0.83V win8 runs faster especially on GPU intensive operations. Cant wait to find a way to undervolt both the i7 and the intel hd3000 as well

 

if i have a 15z, but with i5 2410
would these work and what do they do actually? I'm quite interested but i don't know what i'm getting too? XD

 

I guess if you're asking those questions it's probably better if you don't flash this bios. They're quite advanced and let you do specific things like change memory timings, graphics processor priorities etc, but apply a wrong setting and you may be stuck in boot. Once we've found the way to flash recovery bioses (which actually is gathering momentum at the moment) it would be a better time to experiment with these bioses as it would then allow you to completely recover from any issues.

 

Ohh i though you had come with some ''default modded settings of those bios'' that would be working on every 15z.

The fact that you have achieve to bring the 525m to a 540m was pretty interesting too + the battery life aspect.

 

will you be modding other dell laptops bios?

 

Depends what dell laptops. A lot of good work has been done on bios-mods forums, so feel free to look around and see if someone has already modded your bios. Otherwise feel free to ask.

 

Ive been trying to mod the XPS 15 (L501x) bios. I am able to change the voltages of the video cards and I have a bios from kizwan that unlocks additional menus. Some things I want to try but haven't been able to do/don't know how/not sure if is necessary:

+change video card (GT 420m to 435m or 525m or 540m) (they're all the same chip basically).
+update cpu microcode
+anything else that can enhance cpu performance.

 

sorry I haven't replied to you - am quite busy at the moment.
In response to your queries:

1) Video Card - yes that should be doable assuming you know what the vbios rom is. I had posted a howto in the bios mods forum
2) CPU microcode - in theory yes but I don't know the exact process. It's also messy to do. In fact if someone can show me how to do this effectively it would be greatly appreciated!
3) That's probably two things: (i) enabling hidden menus (ii) using cloverefi to overclock on boot, but you need to be booting in uefi mode. Let me know if you're interested in this as it probably requires another thread

 

I'm also interested on this ^^

 

yep i already have hidden menus enabled. I am also very interested in this cloverefi for overclocking.

edit: from googling, doesnt seem like my bios can have UEFI, but may be unlocked somehow? ugh

 

Will this work with on XPS 15z with i7 2620M? Also, are there any known issues?

Alright, I decided to flash it anyway. So far so good, thank you! However, when video card is idle and downclocks, then voltage drops to 0.83 volts, but under normal/load conditions the voltage is 0.98 volts. Is this how it should be? Or should I observe 0.83 volts under load as well?

 

Just for comparison, I'm running the stock BIOS, and my low voltage is 0.85, voltage under load is 0.95V.

I'm itching to flash this, just because I can, but I don't really understand if I'll get any real world performance gains, or if its just cool cuz it's a mod.

 

Sorry guys been quite busy (again).

With gaming the temperature drops with the new bios because the GPU is undervolted. There's a brilliant thread by captainkasar on the L502x that explains this in more depth (he's using the same mods) so if you use it more for windows and gaming I'd strongly advise you to check out his thread. There's a bug in the nvidiainspector that shows 0.98V but its actually running at 0.85V (I know because I set those limits in the BIOS GPU)

CloverEFI is good if you know how to play around with UEFI and partitioning (and most likely run OSX) - otherwise stay clear away from it for now until a more polished method is found.

With the new bios you will also get some performance boots by tweaks (eg: fast strings, peak turbo limits etc) but you'll have to play around with them and google around a bit!

 

ahhh, ok, I see now how voltages work. Thanks you for this great BIOS mod, Jkbuha, this is super cool!!!

 

jkbuha If you mention in first post for support of CPU in 15 then it will easy for member and they stop asking question.

 

Done Nightmare - thanks.
Out of interest, did you try my modded 15z bios? If so, do you have any feedback?

 

No, not yet. I have i5 2430M and see most of the people having i7 here.

 

Works the same for i5 and i3. On another forum I have had confirmation for both processor families on the 15z

Sent from my HTC One X using Tapatalk 2

 

Make it clean in your first post like:

CPU Support: All i3 series, i5 series and i7 series.

Feature Enable: Under-volt or Over-volt whatever voltage your mentioning. And so on.

 

Done - Apologies for not being that descriptive upfront. I'll add more as we go along.

 

Hi all

I've downloaded and modded the newest A12 bios for the 15z, but I can't upload it here because I don't have enough rights to upload a 5MB file.

Can one of the admins give me rights to upload here?

Thanks
jkbuha

 

I had the same issue with the L502X BIOS files, well I doubt the admins will give us special rights to upload attachments

use mediafire like me or another uploading site ^^


PS: did you finally had luck with the recovery key for the 15z?

 

sadly not yet kasar..

on that note - anyone who knows the bios recovery hotkey sequence for the 15z will help me greatly and help more custom 15z bioses come quicker as well!

 

I have a 15z with the i7, and i've experienced some overheating issues when gaming, can I have this flashed and could it possibly help with the issue?
I did update to the latest BIOS from dell hoping it would help

 

The bios from Dell won't help as it uses stock voltages. Use my modded bios in the first post and you'll definitely notice a drop in temperature.

 

No it can't recently I played NFS MW 2012 and max temperature recorded was 91 C. I'm on A11 dell stock BIOS

 

With NFS MW (o/c'd to 700/1400/920) @ 0.83/0/85V with the modded bios the temp stays constant at 75C.

 

That looks awesome, my Laptop heats up way to fast when playing a game, jkbuha, would you mind sending me the modded bios? i'm new to this forum because i was looking for a way to improve the performances of my dell xps 15z L511z ... So it would be greatly appreciated if you send the file to my email: [email protected] please! oh and if it's not a bother ... explain to me how i should install the bios? because i didn't understand the explenation of your first post!

Thanks!

 

It's in first post, please download from there.

@jkbuha: The new A12 BIOS has been released.

 

Yes A12 has been modded for a month now, and I had posted it on a few other specialist bios modding forums as it had been requested there. Was waiting for someone to request it here as well.

There's an additional surprise in this mod that you won't find in the original A12 bios - an updated Intel HD3000 bios which runs faster and more stable as well.

First post updated.

 

Can somebody tell me how to flash the .WPH file or how to install it to replace my A12 bios?

 

@nati

download

WinFlash for UEFI 1.4.75.0.rar

then open winflash.exe and select the modded wph file, flash it, as simple as that

 

Meanwhile i tried to figure it out myself and what I did was:

I downloaded the bios update file from dell, opened it, and pressed accept whereafter the phoenix program opened, pressed cancel, saw where the temp file with the winflash folder was located, opened that folder, renamed the bios file in that folder to bios1(backup) and copied the modded bios into that folder, and renamed it to bios1 and then chose that file and clicked option "flash only" then i flashed it, it installed the new bios and i don't really know what happened ... how would i notice the difference? should i start up a game and check my core temp? because when my processor is aloud to run at 100% my temperature gets too hot and my laptop shuts down, from what i understand, the modded bios should fix that problem... or am i wrong?
what does the modded bios actually do ...

 

@nati

oh, smart move, I like it

well, the modded bios have unlocked menu and stuff at the bios setup.

look at the advanced settings tab, you should see a lot of new options, including a setting to change bios language.

 

So does Windows 8 UEFI booting work with this BIOS?

 

Yes it should (in theory) though I'm waiting for someone to post a good howto

 

I have installed windows 8 Pro on my XPS 15z, with this Bios and set up UEFI booting.
It is working fine.

 

i mean - are you booting win8 natively via UEFI?

 

Windows 8 installed, went to Boot Configuration -> UEFI Boot = enabled

 

no dude - that means you have the option to boot UEFI, though you're not actually booting UEFI.
Switch off Legacy Boot in Boot Configuration and you'll see what I mean...

 

Do a "BCDedit.exe /enum" and the Windows Boot Manager should say path = \EFI\Microsoft\Boot\bootmgfw.efi. If it does that means you are booting UEFI. I wanted confirmation before I re-install Windows.

 

I just found a guide to convert a BIOS install to UEFI install: Converting Windows BIOS installation to UEFI:

 

I converted to UEFI and it boots faster but after logging in the system completely freezes. Also the keyboard and and right clicking doesn't work in Safe Mode. Don't know what's going on, but looks like I have to convert back to MBR.

 

So I installed Windows 8 from scratch wiping the disk with diskpart clean. It turns out it's QuickSet freezing the computer. Don't install it if you are using UEFI. Everything seems to work and it's booting real fast with UEFI boot enabled.

jkbuha, Do you think it's possible to add SecureBoot into this BIOS?

 

Looking in Device Manager, I have this error now on two devices with this bios (it wasn't present before):
Intel(R) 6 Series/C200 Series Chipset Family USB Enhanced Host Controller - 1C26
Intel(R) 6 Series/C200 Series Chipset Family USB Enhanced Host Controller - 1C2D

 

So QuickSet was working before on this BIOS before I enabled UEFI. Any ideas why it's freezes when I try to install QuickSet? I can't control the state of the wireless with F2 or bring up battery info with F3 without it.

 

Daniel - its because now they are controlled using ACPI not BIOS calls. Did you try playing around with the ACPI options in my unlocked BIOS?