[Samsung Galaxy S 5 Unified Development] curiousrom:
Most Recent Modem = Best Modem? - SM-G900F & SM-G900M

Where do you live?

Your attachment says Build G900FXXS1CQD8 & Baseband G900FXXU1CQB1 and according to updato.com you have the most recent bootloader & modem as seen in this search sorted by most recent for S5 SM-G900F & Saudi Arabia (KSA): https://updato.com/firmware-archive-select-model?q=SM-G900F&rpp=15&r=KSA&order=date&dir=desc&exact=1 May 03, 2017.

Updato says phone for modem (or radio) in their download pages & PDA = bootloader version for the S5 kltexxx family.

So unless you are in a different region I would say you are fine.

haggertk has a Odin flashable bootloader/modem combo G900FXXU1CRH1_G900FXXU1CQK3_Baseband_Firmware.tar.md5 here https://androidfilehost.com/?w=files&flid=142043&sort_by=date&sort_dir=DESC but once unzipped the modem.bin says Modified Thursday, ‎January ‎12, ‎2017 and it's the most recent for S5 SM-G900F region United Kingdom (BTU) August 29, 18.

But then more recent S5 SM-G900F firmwares for other regions have other modems as seen in https://updato.com/firmware-archive-select-model?q=SM-G900F&rpp=15&order=date&dir=desc&exact=1 like for Sri Lanka (SLK) Oct 05, 18: modem G900FXXS1CQAB. Or Greece (Cosmote) (COS) Oct 04, 18, Austria (T-Mobile) (MAX) Oct 04, 18, Czech Republic (T-Mobile) (TMZ) Oct 04, 18, etc: modem G900FXXU1CQC2 for example.

The higher the last 4 alphanumeric characters, the more recent it is but that does not mean it's the best for a given region with a given network provider.

Otherwise why would Samsung use different modems for different regions for firmwares with similar release dates?

They don't say why.

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Bootloader Update?

haggertk said here in the 16.0 beta thread:

But then [MENTION=2693412]haggertk[/MENTION] also posted here:

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S5 SM-G900M

On my S5 SM-G900M klte after trying haggertk's G900MUBS1CQD5_G900MUBS1CQA3_Baseband_Firmware.tar.md5 & doing some thorough testing using Network Signal Info, Network Cell Info Lite and the information overloaded Network Signal Guru & noticing higher Mobile network standby battery usage I returned to modem G900MUUB1CQC1 because it gets better & more stable LTE signal strength in Costa Rica.

I could not return to my original slightly older G900MUBU1CQD3 bootloader (named aboot on the S5) as I got this error in Odin3 v3.13.1 (includes Mac plugin bundle) when trying several times to flash back bootloader/modem combo extracted from the original Samsung firmware of my device:

<ID:0/010> aboot.mbn

<ID:0/010> FAIL! (Auth) - the screen of the S5 said Secure Check Fail : aboot in red as seen in the attached photo

Full Odin3 log:

<OSM> Enter CS for MD5..

<OSM> Check MD5.. Do not unplug the cable..

<OSM> Please wait..

<OSM> Checking MD5 finished Sucessfully..

<OSM> Leave CS..

<ID:0/010> Added!!

<ID:0/010> Odin engine v(ID:3.1301)..

<ID:0/010> File analysis..

<ID:0/010> Total Binary size: 62 M

<ID:0/010> SetupConnection..

<ID:0/010> Initialzation..

<ID:0/010> Get PIT for mapping..

<ID:0/010> Firmware update start..

<ID:0/010> NAND Write Start!!

<ID:0/010> SingleDownload.

<ID:0/010> NON-HLOS.bin

<ID:0/010> aboot.mbn

<ID:0/010> FAIL! (Auth)

<ID:0/010>

<ID:0/010> Complete(Write) operation failed.

<OSM> All threads completed. (succeed 0 / failed 1)

I then created an other .tar with only NON-HLOS.bin (for LTE) and modem.bin and everything is fine after 2 days of testing. (Odin3 modem flashing success screenshot)

That's a hole in the theory that both bootloader & modem as a matched pair should be updated at the same time which I also believe is good thing to do if possible.

So in my SM-G900M case it seems that haggertk's reply to this post does not apply as I can't downgrade the bootloader from CQD5 to CQD3:

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BTW if you go to your XDA profile in this panel https://xdaforums.com/profile.php?do=editprofile and add info > Service provider as it's useful for troubleshooting & it will show when clicking the arrow under the username in a browser > City & Home country & then you will get a flag under your username which gives an international flavor to this thread IMO.

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