Did I brick my T520?

[bonjonno]

I have (had) a very nice T520 running the latest windows 10Pro. Been a wonderful machine for the last coupla years. But cabin fever got me to experimenting with it. I took it slightly apart and blew out all the dust. Still worked great. I decided to try one of these modded bios that clear the whitelist; it had lenovo's ver 1.49 as I recall. the machine restarted after I tried to run the new bios install. It paused for a long time, then booted normally into windows, no change. i tried it again (stoopid) and it went dark. When powering on, the power switch lights and it flashes the two speaker button leds on top left of keyboard a coupla times, beeps softly 5 times, then goes off and repeats the same sequence a number of times. Tried disconnecting the backup battery for 30 minutes, same results. the manual tells me 5 beeps is system board. I'm guessing I fouled a bios rom chip somewhere. Is there a cure? Only because it hurts to have such a beautiful machine that's now dead weight. Learned a lesson anyway.

[kfzhu1229]

There is definitely a BIOS chip on this thing, and it's either a SOP8 or WSON package.
You have 2 choices to deal with a bricked BIOS: reprogram the chip with a USB programmer like the CHI341a (you need to buy), or buy a replacement chip with BIOS pre-programmed on it.
You also need a decent soldering iron or hot air station.
Do you have the discrete graphics variant or the integrated graphics variant? I do have a discrete motherboard toast with fried charging chip on it, so I can harvest its BIOS dump and/or its BIOS chip harmlessly.

[bonjonno]

Hello kfzhu1229, Thanks for the reply. After looking into it further I saw a youtube about replacing the bios chip. It's a tiny part which looks to be about 3mm square and has 8 legs; definitely needs a hot air station and younger eyes and steadier hands than I can provide. Beyond my scope. I've accepted that I blew it and destroyed a beautiful machine. I have the integrated graphics btw. Already ordered a T530 on ebay and am hoping for the best. I will hold on to the T520 just in case. Found a preprogrammed bios chip on ebay for $24. I noticed a T43P in ur sig; I have a T43 somewhere here that looks new. I think it has XP Pro on it. Takes forever to boot and the wi-fi was horrid as I recall.

[kfzhu1229]

Hello kfzhu1229, Thanks for the reply. After looking into it further I saw a youtube about replacing the bios chip. It's a tiny part which looks to be about 3mm square and has 8 legs; definitely needs a hot air station and younger eyes and steadier hands than I can provide. Beyond my scope. I've accepted that I blew it and destroyed a beautiful machine. I have the integrated graphics btw. Already ordered a T530 on ebay and am hoping for the best. I will hold on to the T520 just in case. Found a preprogrammed bios chip on ebay for $24. I noticed a T43P in ur sig; I have a T43 somewhere here that looks new. I think it has XP Pro on it. Takes forever to boot and the wi-fi was horrid as I recall.

For $24 it is really really overpriced... I'd imagine if you can find it for like $5 or $10 it's worth a shot. Otherwise, just buy that CH341a programmer and flash it yourself (buy the latest variant of the programmer with 1.8 and 3V support, and preferbly with a SOP8 ZIF socket).
If you are scared with hot air station and don't have enough precision, and you have the SOP8 package, the alternative is to use a soldering iron (a $15 one from Amazon will do) with both a fine tip and a blade tip.
Since my hot air gun is really cheap and really struggle to melt lead-free solder, I would use the soldering iron, heat up to 400C, tin the legs with a bit more leaded solder to lower the melting temperature, then use the blade tip and melts all 4 pins on one side at once, and then you can slightly lift up the chip with tweezers, and then melt the other side. This works surprisingly well and I've removed a number of SOP8 package BIOS chips and MOSFETs this way without damaging anything.
And, while I can take those chips off (BIOS+EC chips), flash the BIOS dump for a T520 with integrated graphics (I have a fancy TL866 programmer), and send it to you, if you aren't located in North america, the postage may be a bit expensive.
Also note, T530 have lots of differences in the bottom cover - different heatsink (screw mounts), IO ports, magnesium frame, palmrest and that keyboard. Swapping in a bare T530 motherboard is going to be really hard of a task.
And yes I have a T43p, it's sadly retired from my daily laptop because the aging motherboard and frame simply cannot cope with the bends and thermal shock it would see on a regular winter day in my backpack. I made sure to cool the southbridge, and the GPU failed instead, and I had to have the motherboard replaced.

[bonjonno]

Thank you for all the guidance and tips. You've given me the confidence to at least try this. I have a soldering iron w/ adjustable temperature and the needed tips. May need to get a magnifier lamp. Never totally disassembled the T520, but I'll give it a shot. Need to gather lots of containers to keep the parts separated and labeled. Once I get to the system board I can tell you if it is indeed an S0P8 package. I'd very much appreciate if you can send me the programmed chip, but let's wait and see what I need. I'm in South Dakota, US. I'd send you $$ via paypal.

[RealBlackStuff]

Here's a picture with the SOP8 chip-location: http://www.ja.axxs.net/t520.htm
Correction: that's a picture of the T520 EEPROM, NOT the BIOS!!!

If you haven't got it yet, download the T520 manual from the HMM link at the top of this page.
Make a drawing of the screws on the back of your laptop and tape the removed screws on there.
Do the same for inside.

[bonjonno]

Thanks RealBlackStuff. I found that page last night and it's a plethora of great info. Already have the manual. I'm just about to start disassembly. Thanks for the tape tips.

[kfzhu1229]

Thank you for all the guidance and tips. You've given me the confidence to at least try this. I have a soldering iron w/ adjustable temperature and the needed tips. May need to get a magnifier lamp. Never totally disassembled the T520, but I'll give it a shot. Need to gather lots of containers to keep the parts separated and labeled. Once I get to the system board I can tell you if it is indeed an S0P8 package. I'd very much appreciate if you can send me the programmed chip, but let's wait and see what I need. I'm in South Dakota, US. I'd send you $$ via paypal.

DM me for the details for that. And my dead T520 board has the SOP8 chip made by Winbond so all is good here.
Take a picture before you desolder your chip, just in case you mix up the orientation of how the chip goes in.

Here's a picture with the SOP8 chip-location: http://www.ja.axxs.net/t520.htm
RBS-correction: picture of EEPROM, NOT from BIOS

Hmm this is actually good news, as lenovo is nice enough to expose that chip out of the magnesium frame, so technically you need not perform a motherboard removal or cage removal, and just palmrest removal should be good enough.
Guess I can try that lazy method without removing the motherboard first and see if I would damage anything - don't care anyway if it's further damaged as my palmrest has a hole in it and my bottom plastic cover is molten.
Also, is there a secondary BIOS chip or keyboard controller ROM chip for the T520? It doesn't look like so when I see the schematics, but if so I am afraid you would need to replace the other BIOS chip with this BIOS chip at the same time

[bonjonno]

I am in the process of tearing the thing apart right now. It's going great. I'm shooting pics of everything. I am up to CPU removal and have 4 steps to go to be finished. Looks like the bios chip is covered by the magnesium frame, but perhaps not. It'll be a good experience for me to go all the way. I'll pm you when I get there. Thanks kfzhu1229.

[RealBlackStuff]

Oops!
I showed you the location of the EEPROM in which the BIOS password is stored.
The BIOS itself is stored in 1 separate SO8 or WSON8 chip, known as "LILY-BIOS-COLAY-GP-U" and marked as SPI1on the motherboard.

MORE INFO FURTHER DOWN.

[bonjonno]

I've got it completely apart now and only see the SPI1. Still waiting for admin to give me the ability to attach a file. I'll see if I can upload a pic to Drive...
try this

[bonjonno]

OK. Photo didn't take. here's the link. https://drive.google.com/file/d/1eG5Jmg ... sp=sharing

[kfzhu1229]

Oops!
I showed you the location of the EEPROM in which the BIOS password is stored.
The BIOS itself is stored in 2 separate SO8 or WSON8 chips, known as "LILY-BIOS-COLAY-GP-U" and marked as SPI1 and SPI2 on the motherboard.
The chip options can be seen here:

Hmm where did you see that? I am using the ThinkPad W520 schematics and I find no mention of SPI2 inside there at all! Just one SPI1 chip and it mentions the Winbond W25Q64CVSIG as one of the chip options, which is the chip both of us have
Also as the gallery below, I have successfully desoldered the chip without removing the motherboard or bottom cover, though I did mangle the legs a tiny bit and have to bend them lightly against a table.
My suggestion is that you practice this technique on a spare 100% dead motherboard and try to take off its SOP8 MOSFET and BIOS chips a few times. I went a bit too hard here and ripped one pad off the motherboard - not like it matters in my case anyway.
Here are what should be done in my opinion (without a hot air station, and this will NOT work with WSON8 package since the centre ground pad must be removed with hot air):
1. Remove the palmrest
2. Locate that BIOS chip
3. Use fine tip on soldering iron set to 370-400C
4. Apply flux, and also apply some leaded solder to mix and lower the melting temperature of existing solder. Try not to bridge the pins
5. Swap to flat blade tip and heat to 400-450C
6. Apply flux, then heat one side's all 4 pins at once with the flat blade tip. The side of your dominant hand will be easier.
7. Once all the 4 pins have melted, carefuly lift the chip up with tweezers, and then remove the iron. Make sure that the solder no longer rebonds the chip and the board, then rest the chip down once the solder hardens
8. Then heat up the other side, once solder melts, the chip comes loose.
https://1drv.ms/u/s!AuILfFUnTy5cg2di5Zi ... A?e=usYU0R

EDIT: Actually there is indeed a smaller SO8 chip labelled as U30 that's mentioned on all the youtube videos I've seen as the BIOS chip. All the hacks to the BIOS I've seen on youtube for T520 are targeting that U30. So... is that the main ROM or is it just settings like the BIOS password...
Well fortunately, SO8 can also be desoldered with an soldering iron the same way as before, just now the chip is much smaller.
It might be called U22 on the T520 but yeah the chip is around in the same place I believe. I will check once I tear my broken T520 open
While at it, it would help if someone can share a set of BIOS dump ROMs for iGPU T520 with Coreboot and whitelist removal already built in, so that's all done with once and for all

[bonjonno]

The U30 is to the right of the chip we've been looking at. It's likely under the magnesium frame. You can just make it out in this pic. https://drive.google.com/file/d/10b122F ... sp=sharing Really tiny; don't know if I can solder this one. Funny, the people who are selling bios chips for the T520 on ebay all seem to be selling one chip. They all warn that it won't work if you have a bios password, which I do not.

[kfzhu1229]

The U30 is to the right of the chip we've been looking at. It's likely under the magnesium frame. You can just make it out in this pic. https://drive.google.com/file/d/10b122F ... sp=sharing Really tiny; don't know if I can solder this one. Funny, the people who are selling bios chips for the T520 on ebay all seem to be selling one chip. They all warn that it won't work if you have a bios password, which I do not.

Actually, strangely enough, ONLY the integrated variant of the T520 has U30 located right there - my discrete variant (along with W520 probably) has U30 on the flip side of the motherboard!
And I tried desoldering that chip with a soldering iron, and that's a destruction - the lead free solder Lenovo used is extra high in melting temperature and the legs of the chip rips out... So if we need to replace U30, you can forget about using a soldering iron.
Fortunately, it seems like that's NOT the chip you are supposed to replace for bricked BIOS! Yes I also see that all the ebay listings are for one chip and they emphasise that is not for password removal, and I do recall seeing youtube videos with people trying to short out U30 and the laptop still boots fine but with all settings as factory defaults, so this leads me to BELIEVE that U30 is ONLY responsible for BIOS settings, while the bigger SOIC8 chip is the one truly responsible for the BIOS image itself!
I have reached out to one of the BIOS chip sellers on eBay to confirm whether my hypothesis is true.
Also, I really need a BIOS image with known integrated graphics variant of T520... I have seen numerous BIOS dumps of T520 but no mention whatsoever of whether it has discrete graphics or not!

[RealBlackStuff]

I'm getting old...
I must have used the schematics of the W530 instead!
Apologies again!

Bonjonno found the correct BIOS chip.

T520/W520 have the same layout, with only 1 BIOS-chip, marked SPI1
It's one of these 64Mbit SPI FLASH:
SO8: Macronix MX25L6436EM2I-10G
SO8: Winbond W25Q64CVSSIG ----> Bonjonno's T520
SO8: Atmel AT25DF641
WSON: Numonyx M25PX64-VMD6TG

On eBay they sell pre-programmed T520 BIOS-chips: https://www.ebay.com/itm/382092160970


Not specific for the T520, but an overview of how to make a BIOS file and flash it: https://www.partsnotincluded.com/flashi ... vo-laptop/

[kfzhu1229]

Bonjonno found the correct BIOS chip.

T520/W520 have the same layout, with only 1 BIOS-chip, marked SPI1
It's one of these 64Mbit SPI FLASH:
SO8: Macronix MX25L6436EM2I-10G
SO8: Winbond W25Q64CVSSIG ----> Bonjonno's T520
SO8: Atmel AT25DF641
WSON: Numonyx M25PX64-VMD6TG

Okay that's great, and that's also the BIOS chip that I have.
So I guess long story short, there is that SPI1 BIOS chip, and there is the EEPROM chip U30 for all the BIOS settings, and one can get away with swapping just the SPI1 in the event of bricked BIOS.
And while the T520 and W520 have the same BIOS chips and location, it turns out again, the other EEPROM chip for the settings/configs have different locations depending on whether there is discrete graphics! Discrete boards have that U30 chip on the back side, while the integrated graphics boards have that U30 chip right beside the SPI1 chip!
So, in this event, since all the configs and settings are stored on U30, and by the guide you sent, does it mean that integrated graphics variant and the discrete graphics variant have the same BIOS ROM? If that's the case, I don't need to flash anything, since I know the BIOS was perfectly working before I killed my battery IC, and then botched repair killed the motherboard.

[RealBlackStuff]

The BIOS should be identical for iGPU and dGPU, since Lenono only ever supplied 1 BIOS for the T520.
So basically you should be able to easily swap BIOS-chips between any T520 mobos.
That's also why they can sell those BIOS chips on eBay.

[bonjonno]

Thank you both for your time, knowledge and research. The hard part for me will be getting the new part on, but hopefully I'll succeed. My part looks to be a Winbond 25Q64CVSIG, slightly different than RBS' notes. I cannot even see the partially obliterated number with a magnifying glass, but my trusty Nikkor Micro lens came thru. Turns out electrical type soldering flux isn't readily available in my nearest town, so I'll have to order some on amazon. What do you all recommend? SRA 135?

[bonjonno]

kfzhu1229 I sent the money for the chip and shipping; will start practicing my soldering skills. Don't have non working lenovo motherboards or probably any dead mobos but I'll find some components to work on. Thanks for ur help and guidance.

[bonjonno]

I tried to remove the bad bios chip and ended up pulling 2 of the 8 pads completely off the board. One of the remaining 6 is pulled up but still attached. It was suggested that perhaps enough traces exist to still connect a new chip, but this work is way too macro for me to complete successfully. Gave it a shot. Thanks for ur suggestions and help. https://drive.google.com/file/d/1m53gw9 ... sp=sharing