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Properly Clearing CMOS

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from our engineers in Taiwan:

 

Recently we have noticed there are some users having problem with LP UT RDX-200 DR-CF.

 

After we analyzed all available information. We found some users took off battery from motherboard to clear CMOS, However users should use Clear CMOS jumper to clear CMOS. Because LP UT RDX-200 DR-CF has more sophisticated design, and its’ battery provides power source not only to CMOS but also to a Power Controller. This design will allow motherboard to store some important power management settings, such as Vcore and some power protection settings. If users take off the battery on RDX-200, it does more than clear all the value in CMOS, the Power Controller will also suffers from power failure with the consequence of losing all the default setting stored inside.

 

Therefore let’s say it again, we strongly urge our users, “If you need to clear CMOS, please use Clear CMOS jumper to do so. Do not remove the battery on motherboard for clear CMOS purpose!”

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Guest dodo

Interesting. My procedure had been always put the jumper to clear position, remove battery. Put back battery in, setup clear cmos jumper back to run.

 

What power management settings would that be? And how would the power management form one CPU be applicable to another CPU. Wouldn't you want that setting also be cleared???

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Uh, how are you supposed to change the battery after it becomes empty?

 

You have to re-flash the BIOS after every battery failure?

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Ok after having been there and done that many times when first reading cryptic engineering statements in my english language from one normally thinking in another language> I have learned never to go to the side of the bridge and jump immediately.

 

I think I actually read this and on further examination find it to be so for the cryptic engineering statement above and the RDX200. We are testing to see what if any relationship might exit between battery removal and cmos jumper pin movement to the clear cmos position.

 

Knowing that the general consensus has been to remove the battery and move the cmos jumper at the same time to clear the cmos on a DFI board; it is suggested during the time while engineering is doing their checking to refrain from removing the battery JUST to clear the cmos. It should not be necessary to remove the battery when trying to JUST clear the cmos on the RDX200 board as has been presented as a step in clearing the cmos on previous versions of boards. Leave the battery in and just move cmos jumper to the clear cmos position with a/c power removed from the power supply should you need or have occasion to clear the cmos.

 

Even shorter version. If you should find yourself in great need to change out a cmos battery on a board only 2 months old, when batteries usually last for years; change the battery. If your procedure to clear cmos with previous DFI boards has included removing the 'battery' and moving the cmos jumper to clear position> leave the battery in the battery holder and move only the cmos jumper to the clear position with A/c power unhooked from the power supply. Leave cmos jumper in the clear position for a minute or two then jumper the pins back to the normal run position and repower up the power supply and on to the business of computering.

 

This in my best red-nake english, is what the cryptic engineering statement said. They are doing lab testing. They suggest I leave the battery in and not take it out if I am only clearing cmos. Move the cmos jumper only. If I want to change my battery; to change my battery. They will give me another cryptic statement later.

 

Now that is what I read and after further checking found I was correct. Later.

 

RGone...

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Well, the question is still what happens to the BIOS defaults (not the user settings). If what DFI Taiwan says is true and they are lost when you remove the battery that is a serious issue. It would require that you re-flash the BIOS after taking out the battery. I doubt this is what happens.

 

In that case, the only way to change the battery for a new one would then be to change the battery while the PSU is connected and powered and the board is soft powered off, so that the defaults (not the user settings) survive on external power.

 

Of course that is still useless if you happen to have a dead battery.

 

Overall, I don't think that what we make out of the DFI Taiwan statement above is quite accurate. If it is of any help, I have several Chinese engineering friends here in Boston and we would be happy to provide a translation for a Mandarin statement that DFI Taiwan writes.

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Btw, I think most of us who purchased this board will probably upgrade even before the battery dies... LOL

 

Anyways, I never had to remove the batt to clear cmos on my CF-DR. The clear cmos jumper works well for me.

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Remember all - Beta Bios's will void warranty

 

 

How come DFI's engineers suggest to put latest bios (in RDX200's case it's been always beta-bios) in before they have thought other problems?

 

Kind of conflicting I think :confused:

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Guest dodo
Ok after having been there and done that many times when first reading cryptic engineering statements in my english language from one normally thinking in another language> I have learned never to go to the side of the bridge and jump immediately.

 

I think I actually read this and on further examination find it to be so for the cryptic engineering statement above and the RDX200. We are testing to see what if any relationship might exit between battery removal and cmos jumper pin movement to the clear cmos position.

 

Knowing that the general consensus has been to remove the battery and move the cmos jumper at the same time to clear the cmos on a DFI board; it is suggested during the time while engineering is doing their checking to refrain from removing the battery JUST to clear the cmos. It should not be necessary to remove the battery when trying to JUST clear the cmos on the RDX200 board as has been presented as a step in clearing the cmos on previous versions of boards. Leave the battery in and just move cmos jumper to the clear cmos position with a/c power removed from the power supply should you need or have occasion to clear the cmos.

 

Even shorter version. If you should find yourself in great need to change out a cmos battery on a board only 2 months old, when batteries usually last for years; change the battery. If your procedure to clear cmos with previous DFI boards has included removing the 'battery' and moving the cmos jumper to clear position> leave the battery in the battery holder and move only the cmos jumper to the clear position with A/c power unhooked from the power supply. Leave cmos jumper in the clear position for a minute or two then jumper the pins back to the normal run position and repower up the power supply and on to the business of computering.

 

This in my best red-nake english, is what the cryptic engineering statement said. They are doing lab testing. They suggest I leave the battery in and not take it out if I am only clearing cmos. Move the cmos jumper only. If I want to change my battery; to change my battery. They will give me another cryptic statement later.

 

Now that is what I read and after further checking found I was correct. Later.

 

RGone...

 

Hi,

 

I just confirmed that the battery removal does have an impact on the Voltage bios bug.

If you remove the battery with or without the clear cmos jumper OR have a BRAND NEW board - it both has an impact.

I initially didn't believe in the battery bit since I had the voltage bug with 2 boards without having removed the battery in the first place - one of the boards was a RMA board from DFi - the other one brand new board .

 

I guess someone @ DFI must have also used the battery removal procedure before the tested RMA board was sent to me :rolleyes:

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