[REQUEST] Dell Precision T3500 BIOS Unlock

[Sml6397]

Alright, we will try to figure this out! The attached pictures are great.

Here's the CH341A package I ordered: https://www.amazon.com/gp/product/B07V6W...UTF8&psc=1

The clip works great for some people and not very well for others (I am one of the latter). It is sort of cheaply made. If you have problems with it, you may need to order the Pomona 5250 clip. It gets a really good grip on the BIOS chip. You probably won't need this though. Here is the one I ordered: https://www.amazon.com/gp/product/B00HHH...UTF8&psc=1

If you additionally order the Pomona 5250, you will also need to either solder the cables from the old clip to the new one or you will need to order 8 female-to-female jumper cables. I recommend a wire length of at least 40 cm for good reach.


The Latitude notebook seems to implement Intel BootGuard technology, which - when properly implemented* - makes it impossible to change a single byte where it is implemented in the BIOS image without creating a brick. If my understanding is correct, BootGuard involves the burning of public key hash into a once-programmable region of either the CPU or the chipset. The public key hash is used to verify that the public key stored in the BIOS image is correct. The public key in the BIOS image is used to verify that the BIOS image on the BIOS chip was created by the manufacturer and not modified from creation to flashing. The BIOS Setup Utility part of the BIOS image (the part used to make edits to the menus and settings) is part of the protected area of the image.

Without Dell's private key, we cannot modify a BIOS image that properly implements* BootGuard without creating a brick. This doesn't stop us from modifying the hidden settings via RU.EFI though! I can post more information on this later on. Basically though, I will provide you with a file that contains a list of hidden and visible settings, as well as what they can be set to, and then you can tell me which ones you want to edit. I can then tell you which variables to edit with RU.EFI.

*To test if BootGuard is implemented properly, please see BDMaster's posts (#7 and #9) in this thread: https://www.win-raid.com/t8865f54-Reques...menus.html Please post the meinfo results here.

Starting today, I will be very busy over the course of the next 9 days, so I will have limited time to work on BIOS mods. I will keep you updated throughout the modification process.

[StarPrince]

Hello Sml6397,

the thread #7 download link isn't working, can you find me an alternative,
btw, i read the whole thread and i found that they post Backup tools ver.20 , it worked for me, you can check it out:

https://www.sendspace.com/file/e5msrr

[ITronLegends]

Hello this is the first time using this forum so yeah..anyways I hope you can add this uefi and maybe secure boot? The t3500 has tpm 1.2 so it kinda supports windows 11. Hoping to see that it works and maybe when your done upload it to archive.org?
Dell is so dumb..like the last t3500 were made in mid 2012 I think and had warranty for 5 years... Like why Dell why... Oh and the t3500 has diff Mobo as well.

How about try using a t3600 Bois to mod the t3500 Bois as the t3600 has UEFI and maybe secure boot too.
T3600 Bois : https://www.dell.com/support/home/en-pk/...erid=knnmy

[Sml6397]

Hello StarPrince and ITronLegends,

Thank you for your continued patience. I recently got back from vacation. MEInfo is still tripping me up, however. Once I figure out how to get it running on my laptop, I will instruct you on which version to run on yours' and how to do so.

@ITronLegends,
These notebooks potentially make use of Intel BootGuard. If they do, then we cannot perform BIOS mods on them, or else we will get a brick. MEInfo will allow us to see if Intel BootGuard is actually being used. If it is in use, we can still use RU.EFI to edit individual settings.

~Steven

[StarPrince]

Hello Sml6397,
Thank you for your continuous follow up, and welcome back from vacation,

I am waiting and trust your work will make a solution for this

btw, the last comment made by ITronLegends provided a bios T3600 that is related to a Workstation PC , the newer brother to this one T3500, it is not a notebook, hope this info makes any addition to you lol.

Attached Intel ME info from my notebook Dell Latitude 3340, if this bios can make any help!

[Sml6397]

Hello StarPrince,

Thanks for this information and the reminder. I will get back on this again. Vacation was fun!

It looks like BackupTool didn't work. Did you order the CH341A programmer? If so, could you get a full BIOS chip dump using that? In fact, get two of them so that I can compare them and make sure that they are consistent with each other. I'd feel more comfortable experimenting if we have a sure-fire backup to use if anything goes terribly wrong.

For now, I will begin looking at the stock BIOS image again.

[StarPrince]

i didnt find the one you have available atm

should i order this one

https://www.amazon.com/-/ar/dp/B08KG7YM4...YM45&psc=1

[Sml6397]

Yes, that one works perfectly.

[StarPrince]

ok , i purchased it but it will take time for shipping, sorry for inconvenience
if there is anything else to do in between let me know
Thank you

[Sml6397]

No worries!

I haven't gotten a chance to begin looking at Dell Phoenix modding yet, but I should by the time your hardware programmer arrives. With the official BIOS update, I should be able to do any learning I need to do. I will replicate any mods I do to it on your BIOS backup.