X48 bios set up

Thank you HellvisPresley, you are a LIFESAVER.

Hi Hellvis.

Just wanted to say thanks a lot for this doc. It looked like my x48 was dead after a battery change.
All's right with the world now,
Thanks a lot : )

This bios information is absolutely invaluable to save you hours, or even days or weeks to get your X48 back online quickly and painlessly!! Thanks for digging up the info and posting for all to use! This is exactly how forums should work!! Cheers!
Thank you very much, nice catch!
I had to go through this all by myself once, it took me at least an hour to sort the bios out and I only managed because I'm actually a PC tech and I'm used to the mystical lingo.
If I remember correctly, the internal HDD doesn't reappear until you reactivate the external SATA controller and reboot.
And there are a few other settings to change from default, namely the drive boot sequence, or you'll have to unplug any external drive each time before booting.
I really dont understand why they didn't rig up a working "default settings" recall in their firmware, I'd gladly do it for free for them, it would take 5 minutes if they sent me the files...
The X48 is such a superb machine, I'd be proud to contribute ;o)
This .pdf will certainly come in handy when I'll have to change the battery again 4 years from now... it will be sorted in under a minute.
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Let me say that this smart work saved me from an unnecessary repair. Thank you, thank you, thank you. Now, can someone explain why the X48 can go into stupid mode when not used for awhile, in this case, 4 1/2 months. I own 2, the other was not used in over 6 months and it booted just fine. Anyone?
Thank you so much for this work and post!
My X48 just stopped booting a few days ago and this info brought it back to life.
here is another


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Yes, I do have 84 pgs Service Manual + 60 pgs Schematic diagram.Is it forbidden to give informatio to the x-48 owners by using tascam forum?
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It's not forbidden. You kept attaching just the first page of the manual in different parts of the forum, which why I asked if you had the full one that we could possibly upload here.
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Hi @grazygear
Could you please share the service manual and schematics for the X48?
You never know when it'll come in handy...
I already have one unit with a fried FireWire port, and the schematics would really come in handy to see if it's something I can sort out myself.
Thanks and cheers!
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I wish I had found this thread before. Just had the same symptoms on my several years old x48. I was going to take it up to Dallas to get it fixed, but bought a new x48mkII this week because I have some recording to do. The mkII arrived with the exact same problem ... fails to boot. I guess I'll go look for a battery for this tomorrow and try the bios changes.

The bios on the X48MKII is password protected. It doesn't accept 'admin'. So, I can't even try this fix on the new machine.

well, I did get the old x48 working. Appears the disk drive may have failed. I installed a new one, and with the procedure described was able to get the OS installed and booted. I wonder if the mkII uses that same password suggested in the procedure for the old x48. btw, I installed 2 2TB disk drives, while I was at it. There was a spare sata port, so now I have back-up in the case. Two of the WD Red drives.

well, it turns out they used the same bios password on the mkII as suggested in the older x48 document. They have AHCI option, but have the sata set for IDE, which seems weird. Anyway, mine didn't detect the master disk at all in the bios. I pulled off the case top, and found the power cable unplugged from the drive. So now I have a back-up system and don't have to drive to Dallas.

got up this morning and the old x48 had cmos checksum error. It restored defaults which don't work. So replaced the cmos battery ... it was cr2032 3V, as you said. I set up the bios again, and now it boots ok again. Battery holder just had a little metal clamp on one side that you push aside. I used some needle nose pliers to hold it open. Used a magnet to lift out the battery since it is kind of tight spaces.

Tested the drive recording speed ... good for something like 150 channels at 96khz ... so no problem there. The second internal drive speed not testable with their software. I will just use it as backup.
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Went to power up my x48 yesterday and it would come on. I assume it's a power supply issue. I bought it new in March 2008 and haven't replaced the cmos battery. I assume this needs to be done too and with the hand written instructions I hope I will be able to get the machine to boot after the install.

Does anyone have a good replacement model number for an after market power supply?
Hi All,

What are the BIOS settings for x48mkII?

I do not speak English very well, thank you for all this information. Can you give me the password for bios X48 please? A big thank-you !!
Tascam X48 was dead in the water for months till I found these docs. Was up and running in about 5 min.

Thank you Grazygear!!!!
Hi , I'm getting blue screen on my tascam X48 MKII , error message : windows detected problem and shutted down....." , so I'm looking for bios setup for it or any advise , thanks

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