Thinkpads Forum

First I'd like to give you guys a shout out! I've been lurking for a while and have learned a lot. Thanks!

I have a T420 and I: a) don't want to give up the keyboard and b) need to get another year, or two of service out of it. The first thing that needs to be sorted out is the WiFi, but I am hoping that someone can clarify the whitelist situation, before I actually spend all the money. But first, what am I trying to accomplish?

I wish to remove the original Intel 1/2 mini 6205 card from the WLAN bay and replace it with either an Atheros QCA9880, or QCA9882 full size mini PCIe card (Yes, I'm running Linux annnd loving it! ). Being full size, the Atheros card would, therefore, need to live in the WWAN bay.

Thanks to you guys, I am aware that there is a whitelist for WLAN devices. What I am not quite clear on is if there is also a whitelist for WWAN devices, or if there is just one big whitelist, regardless of which mini PCIe slot is used. One would assume the latter, but common sense does not always apply. Most importantly, if I source a BIOS with the whitelist removed, does this remove the entire whitelist, or do I need to specify that I intend to use the WWAN bay for my perverse WiFi pleasures?

Also, I don't know what I don't know. So, if anyone sees an obvious problem with this plan, I'd like to hear from you!!!

Thanks in advance!

A whitelist modded bios will remove all restrictions on mPCIe devices. You'll be able to run anything that's electrically compatible in any of the slots.

Putting a fullsize card in the WWAN slot should work fine.

The only hitch I'm aware of is that it seems like it may not be possible to downgrade BIOS versions on these machines (at least that's how the BIOS descriptions from Lenovo make it sound), in which case you'd need to find a modded bios version that's the same as or newer than what you're currently running. Slightly older modded BIOSes are easier to find, but I think even the most recent BIOS version from Lenovo has been modded. It might just require more digging to turn it up.

You will not be able to use a PCIe card on the WWAN slot, as only the USB (for the WWAN card) and SATA (for the mSATA SSD) signals are wired to the connector. This means you'll have to use a half-size card.

Sweater Fish Deluxe wrote:A whitelist modded bios will remove all restrictions on mPCIe devices. You'll be able to run anything that's electrically compatible in any of the slots.

Putting a fullsize card in the WWAN slot should work fine.

... it may not be possible to downgrade BIOS versions on these machines ...

Thanks for your reply. I'm running the v1.46 BIOS, so if I understand correctly, I should be good.

axur-delmeria wrote:You will not be able to use a PCIe card on the WWAN slot, as only the USB (for the WWAN card) and SATA (for the mSATA SSD) signals are wired to the connector. This means you'll have to use a half-size card.

Ah, thanks for the correction. I thought this only applied to the T60 generation and that beginning with T61 all the slots were fully wired.

I did just test the full size slot on my T420s and it does not recognize a mPCIe wifi card. Good to know, I guess.

Kielbasa, I stand corrected. You'll have to find a half size AC card.

axur-delmeria wrote: ↑

Tue May 02, 2017 1:12 am

You will not be able to use a PCIe card on the WWAN slot, as only the USB (for the WWAN card) and SATA (for the mSATA SSD) signals are wired to the connector. This means you'll have to use a half-size card.

Thanks so much for your reply; this is a tremendous help!

I looked high and low and I finally found a 1/2 mini card based on the Atheros QCA9882 2x2 AC chipset. They are very difficult to find in full size mPCIe, but just about as scarce as hens teeth in the 1/2 mini format. SparkLAN just got them in stock, in the event that there are any other Linux/Unix/BSD folks out there, who are interested.


Thanks again for your help, everyone!!!

I have a modded version of the v1.46 BIOS installed. I use the 6300 card and it works much better than the stock card. It connects immediately and never drops the signal.

MikalE wrote: ↑

Tue May 02, 2017 8:10 pm

I have a modded version of the v1.46 BIOS installed. I use the 6300 card and it works much better than the stock card. It connects immediately and never drops the signal.

Yeah, the original card has not been brilliant. Mine went through a period where it would drop the signal and then not be able to reconnect without rebooting. Checking through the logs, I saw that it was actually dropping the signal a dozen times an hour, but it was automatically reconnecting 95% of the time. I literally tried everything that I could think of and I never got to the bottom of it. Then, just as mysteriously as the problem began, the problem went away?!?!?!

What is your range like on the 5GHz N-band of the 6300 card? I tried an Intel 5300 in a Dell laptop and the line-of-sight range was extremely poor. I even replaced all three antennas with 5GHz-specific units, but going through a single internal wall of the house caused the 5GHz signal to completely crash and burn. Even with line of sight, the 5300 was actually faster on the 2.4GHz G-band at anything more than 15 feet, or so.