05-04-2016 02:21 PM
got a T520 here (nVidia GPU) which constantly restarts and never reaches the Welcome Screen of the BIOS:
- power button LED goes green
- fan rotates and optical drive is accessed
- fan stops, LED switches off
- approx. one second pause and the whole sequence starts again
This happens both with the power supply and on battery. HDD is removed.
I've already detached the optical drive and the BIOS battery.
Any more ideas? Could this be the result of a failed BIOS update? Or some UEFI variables screw-up?
Is there a crisis recovery procedure for the T520 to update the BIOS from the boot block?
Solved! Go to Solution.
05-04-2016 02:33 PM
A few questions.
05-04-2016 02:46 PM
> Are you pressing the F1 key repeatedly upon powering up the system, and if fi you do not, will it still boot to Windows normally?
I don't have the original HD here, all my trials are without a HD. Pressing F1 during power up doesn't change anything.
What happens if fast startup of Windows 10 was configured and the HD was removed afterwards?
> Did you recently try to update the BIOS prior to this problem occurring?
The T520 belongs to a friend, I have to check with him.
05-04-2016 03:14 PM - edited 05-04-2016 03:19 PM
Windows is not even in play when you try to enter the BIOS, so Windows 10's Fast Startup feature is not the cause. Even without a harddrive, you should still be able to enter the BIOS/Settings at startup, so my guess is that either the main System Board went bad, or BIOS update failed....which unfortunately both would probably require a new system board to fix.
Any chance that it is still under warranty?
05-04-2016 03:49 PM
If you have 2 DIMMs (memory), try them one at a time
05-05-2016 04:14 AM - edited 05-05-2016 04:16 AM
Thanks for the reply! I wasn't sure if the Fast Startup feature doesn't reconfigure UEFI BIOS, e.g. by setting some variables, in order to circumvent the normal welcome screen.
No, the T520 is out of warranty.
I've already reflashed the BIOS chip of several Thinkpads (X200s, S430, T400) with a RaspberryPI (using flashrom), some jumper wires and a Ponoma clip for SO-IC8, so that isn't a big problem. Just a question of enough time to disassemble the device and extracting the image from the official BIOS update files. I'll try this soon.
Yes, it has two DIMMs. I'll try with only one of them and with none. Thanks!
05-08-2016 06:03 AM - edited 05-08-2016 06:03 AM
I've reflashed the BIOS region in the SPI flash (offset 0x500000, length 0x300000) and the error is gone!
BIOS version is 1.42, the source for the binary was the .FL1 file from the Lenovo BIOS Win7 update (same offset as above).
The only problem was that the SPI flash came with WSON package, so I couldn't use the Ponoma clip and had to solder some wires.