EP35C-DS3R BIOS o/c not active

[A320]

Trying to overclock a friend's rig with a Gigabyte GA-EP35C-DS3R mo/bo.

I can set FSB to 400MHz in the BIOS via the MIT and save with F10.

The PC boots normally and starts Vista but when I check in sys info or CPUz the FSB is at 333 MHz as if the PC has reset the BIOS back to default settings.

Go back into the BIOS and the FSB is still set at 400MHz so the PC has not reset back to default.

What's going on??

I have exactly the same rig and mine runs fine at 400 FSB.

 

[RGone]

Do both configurations have the exact same ram and cpu?

You could take pictures of your bios setup and the other computers bios setup to ensure that 'both' have the exact same settings. If they do have the exact same settings there could be a failure to overclock to 400FSB and one of the boards is resetting itself to "good" but lower setting and continues onward to boot.

 

[A320]

and one of the boards is resetting itself to "good" but lower setting and continues onward to boot.

That's what I thought but it's not the case. After a good boot if you go back to the BIOS the FSB is still set at 400 so it looks like the BIOS is saving the settings but for whatever reason that is not translated into Vista.

I know when I was trying to push my rig if I went too far it would double POST and reset the BIOS back to standard settings, this one is not doing that.

If no one comes up with a 'Eureka' answer I might try updating the BIOS but I think both rigs have the same BIOS version.

Thanks for the input anyway.

 

[RGone]

Page #51 of the manual for that motherboard:

CPU Host Frequency (Mhz)
Allows you to manually set the CPU host frequency. This item is configurable only if the CPU
Host Clock Control option is enabled.The adjustable range is from 100 MHz to 700 MHz.
For an 800 MHz FSB CPU, set this item to 200 MHz.
For a 1066 MHz FSB CPU, set this item to 266 MHz.
For a 1333 MHz FSB CPU, set this item to 333 MHz.

If that is the location where you are changing to 400FSB, it would be an immediate 20% overclock. Few cpus will just overclock like that without adding Vcore.


What I am doing is thinking outloud or by keyboard. I don't think there is a 'eureka' moment coming.

1. I have seen a few boards that having a failed overclock would just lower the setting but leave the failed clock in the menu as if it were still using the overclocked number. I don't know if that is the case with your situation or not. Looking for the 'eureka' we found it time.

2. I would flash the bios to a newer version just to see what 'might' happen.

3. Later bios 'might' have opened up or loosened some setting that could allow that immediate 20% overclock.

4. It is a slim chance the bios is corrupted in some part of its' code and usually when flashing a bios it erases the previous code and then writes the new code and if the bios were partially corrupt...flashing should cure that ailment. Most bios flashing instructions that I have seen written up in forums say to remove power from power supply and then clear CmOs after bios flash and then hook-up power to power supply again and boot to bios and Load Optimized Defaults save and exit to get bios into default mode.

Beyond that, happy 'eureaka' hunting. RGone...ster.

 

[A320]

Again thanks for the input.

When o/c'ing mine if I went too far or insufficient core voltage then the rig would double POST and reset the BIOS back to default settings but the o/c settings would be held but greyed out. Basically the Host clock reverts to auto from manual.

I could understand it if this rig did that but when it POSTs and boots normally and maintains the 400FSB and host clock at manual then that gets to WTH?

I'll see if a BIOS update cures anything.

 

[RGone]

Yes, by all means let us know the outcome. It lets us know what is the answer in these super odd situations. Have seen something "like" what you are seeing but maybe not exactly. We find out how and with what to help when we get the results from testing that is done by those with a problem. Good luck with bios flash.

 

[A320]

Sorry for the delayed reply but only just got round to updating the BIOS.

Bios is now F4 (was F2) but no change in the o/c status.

Host clock is enabled and FSB is set to 400 in the Intelligent tweaker and the settings are saved but computer properties and CPU-Z still show host clock as 333 and CPU running at 3GHz.
I have now run out of ideas. I build my own PCs (and this one) and have o/c'd many of them but have never had this problem.