Hi Samuel. Yes, that would be definitely the best and easiest way but in the BIOS of this HP (eventhough updated to the latest version) it is not possible to change the boot order. I can ask the BIOS to boot from usb but I can not tell it to load the SSD before the HDD. Probably a skilled guy would make it but I did not manage to find a way to do that, neither others that did that on the internet. That is why you need a sata/usb cable/Gparted/whatever to whipe the HDD containing the old OS with this computer.

I am sure that it is possible to change the boot order in your T420, so you won’t have this problem. By the way, beautiful machine ! Once mine stops I would take one of those. Probably you know it alrealdy, but it can be upgraded and modded completely, cheers!

Hello Ashwin. Once you plugged in the SSD, and before booting the OS, you could try to create a partition in it using a bootable USB stick and GParted or similar softwares. That mSATA door is intended to be a 32GB cache drive only. That should be why the OS cannot recognise such a big drive there. If you create a partition in the SSD, before booting the OS, the latter should manage to see it as a normal drive as you want it to and as it did in my case (I never tried to plug in the SSD and to boot straight away, without creating a partiton there first).

I am not that expert and I can think only of this. Eventough I did another thing from what you’re trying to do, the steps above worked easily for me so that is probably due to something simple you only need to figure out. It should work on your hp envy as well.

This thread could help or you can try to create a thread directly in the iFixit forum.

In my case, the black screen disappears when I boot for the second time. If I reassemble the laptop and put both drives at the same time, and I try to boot, it never boots and that black screen with that message always appears, no matters how many times I reboot. I have to boot once with the SSD only and then I can reinsert the HDD and finally boot the whole system.

Following this reassembling procedure is ok to me, I do not need to disassemble the drives often and the fact of launching the system once, with the SSD only before being able to reinsert the HDD, looks only like a small drawback in reassembling the laptop to me. But I understand that if you need to disassemble the HDD often, it becomes annoying.

If you try this workaround again, be sure that the BIOS is updated and that the HDD you reinsert has no trace of operating system. In any case I do not know if there is a solution to this fact that we always have to boot once with the SSD only before reinserting the HDD at each laptop’s reassembly.

In my case, the workaround I described in this guide works perfectly since last January. It has only this drawback: every time I have to reassemble the laptop - after cleaning / thermal paste or whatever - I have always to boot once with the SSD only, before being able to insert the HDD again and get my whole system back.

So, every time I have to reassemble the laptop, I follow this procedure:

- I insert the mSATA drive (in which Windows is installed).

- I switch on the laptop. (Windows launches as normal)

- I switch off the laptop, I disassemble it, I insert the HDD and I reassemble it.

- I switch on the laptop, I get a black screen with this message or something similar: OS not detected, please install an OS on your Hard Disk Drive and I switch off the laptop.

- I simply switch on the laptop once again, and I get my whole system back with both drives working as desired. Since this time, in which it made it, every time I switch on the laptop the system launches perfectly with both drives and no conflicts.

Hi Raj

we can not change the boot order in the BIOS of this HP laptop series. That is the problem I think, but I am a beginner and not an IT expert. If we could set the mSATA drive to be loaded before the hard disk drive, the problem would be solved, once and for all, and you could remove the HDD as many times as you wish, without boot problems.

If I understood well, you wrote Then later i put both ssd and hdd… And installed Windows again on ssd it worked and i can now see both drives… But again if i take out hdd and try to boot only from ssd .. Then again i can’t boot so you managed to install Windows on the SSD, to launch Windows from it, and to see both drives in Windows ... I do not understand why at that point, if it works, you take the HDD out again.