Which battery for "overpowered" M15X?

No, I'm using a new SSD. The owner before installed Windows 10 and everything on an HDD but I now replaced it with an SSD and install Windows 7 fresh again. Boot times are now about 40-45 seconds...

 

I would keep the custom svl7 vbios. It was designed to make the card run optimally in the M15X and also to allow easier software overclocking.

Even if that vbios is causing the slower boot times (I personally think it's something else), it is still worth keeping that vbios.

https://www.techinferno.com/index.p...king-editions-modified-clocks-voltage-tweaks/

You may want to troubleshoot why your boot times are slow before doing a fresh install. Start with the built-in Dell hardware diagnostics accessible from the boot menu (press F12 on splash screen). Then proceed with a hard drive diagnostic test on both the SSD and the 2nd hard drive. Make sure the AHCI interface is selected in the BIOS. You may also want to remove the 2nd hard drive and see if that speeds things up.

There are lots of factors that can contribute to slow boot times, some software related, and some hardware related.

 

The Dell diagnostic tool told me that everything seems to run fine. Then I made the longer "Memory" test with took about 30 minutes and following message popped up: : No Diagnostic Utility Partition Identified, press Enter to restart your pc now.
CrystalDisk Info also found no failure on the SSD or HDD.
Is there anything else I can do? I don't want to remove the HDD because I have to dissasembly the whole Notebook to get access to it...