So I thought I'd be clever and lower the clock speed in the BIOS. I turned it down to 2.15Ghz from 2.8Ghz.

Now I cant get past the first screen on boot...no warnings...nothing???

As soon as I confirmed the new speed (to reduce power consupmtion and heat) the computer shut down and wont even allow me to get back into BIOS!!! Any way to escape???

I'm writing this from the local library. :(

Did you try tapping the "F8" key when it started up?

Did you take the battery out and put it back in?
Is there a jumper to reset the BIOS? Too obvious.

Did you take the battery out and put it back in?
Is there a jumper to reset the BIOS?
Its a desktop...no battery.
Jumper??? Where?

Did you try tapping the "F8" key when it started up?
I'll try that when I get home, thanks.

If you need to reset the BIOS then look at you mb for the model and check the manual. Most desktop boards have a battery, taking it out and putting it back in may get you into the BIOS screen.

http://www.google.com/search?q=jumper+to+reset+BIOS&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a

If you need to reset the BIOS then look at you mb for the model and check the manual. Most desktop boards have a battery, taking it out and putting it back in may get you into the BIOS screen.

http://www.google.com/search?q=jumper+to+reset+BIOS&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a
Good link...I'll study that and try the battery idea. Thanks!

Oh, do I remove/replace the battery while the computers running or off???

Off. Take it out and wait a few minutes, same for the jumper. Unplug the power and then press and hold the power button for a few seconds.

I am not sure if all mb's have a reset jumper though. I never change clock speeds either.

Here is another link that may help.

http://www.google.com/search?hl=en&client=firefox-a&rls=com.ubuntu%3Aen-US%3Aunofficial&hs=m6M&q=changing+clock+speeds&btnG=Search

Excellent...I'll try the battery idea tonight first, and then the jumper switcharoo.

Report back tomorrow. :rolleyes:

Hehe--- has enough knowhow to underclock the CPU, but has no idea that there's a battery on the motherboard. You would make a great saboteur.



If you aren't getting any POST messages or beeping, you may have killed your motherboard. Hopefully, removing^inserting the battery, or toggling the "clear CMOS" jumper will set it back to its default settings. A lot of boards nowadays detect the CPU and auto-set the relevant settings (IE - BUS speed, voltages and so on). As a safety precaution, the board will become unbootable if the CPU doesn't support the settings.

.....of course, SOME allow you to override those settings so you can nuke your board anyway.

Hehe--- has enough knowhow to underclock the CPU, but has no idea that there's a battery on the motherboard. You would make a great saboteur.

I knew where the battery was, but I didnt know where JP14 was at...had to poke a flashlight in there and snoop around.

I finally found the manual...:eek:

I had to unplug the ATX power terminal, short pins 2 and 3 for a moment and then slide it back on 1 and 2.

Now it works...but I'm still clueless as to how I can underclock without crashing it???

John...you just saved me an expensive trip to the geek stop, thank you!

Is this true that MOST CPUs are 'frequency locked'???

"Most CPUs will be frequency locked, unless you bought a special unlocked version. Most BIOS types auto detect the FSB and multiplier options, although some allow a limited control.

Also, regarding the other point , changing your BIOS options to such a state thats its unstable, ie dram timing, could potentially cause it to crash while writing to the hard disk, which in theory could cause windows to fail to load."

they are called: CPU multipliers

these have unlocked CPU's:

AMD FX-series K8
Intel Extreme Edition
AMD Opteron
AMD Althlon MP
Intel Xeon (?)
Intel Pentium II (pre August 1998)
*all CPU's before the Pentium II*

As I read it...it is extremely hard to change the frequency...unless you are totally committed into cracking it.

these have unlocked CPU's:

AMD FX-series K8
Intel Extreme Edition
AMD Opteron
AMD Althlon MP
Intel Xeon (?)
Intel Pentium II (pre August 1998)
*all CPU's before the Pentium II*
Ah, mines a Pentium 4.
So maybe its frequency locked...hence the crash.

Ah, mines a Pentium 4.
So maybe its frequency locked...hence the crash.

its most def. locked.

* change FSB: Front Side Bus

While Dell offers no overclocking options whatsoever in the BIOS and in fact uses a PLL that was supposed to be designed to not modifiable, it turns out that one can still overclock.

Step 1) Check to see if the Dell uses the ICS 952601 PLL. See either:
http://www.podien.onlinehome.de/FSB.HTM
http://mitglied.lycos.de/podien/FSB.HTM
for more information.

Step 2) Download and install cpucool available from:
http://www.podien.onlinehome.de/CPUCOOL.HTM
http://mitglied.lycos.de/podien/CPUCOOL.HTM

Step 3) Run cpucool and go to Functions->Change front side bus/change CPU speed

Step 4) Under PLL manufacturer, pick ICS and under PLL type, choose 952607

Step 5) Click on the Fine tuning button

Step 6) Adjust the Frequency using the buttons at the top and adjust to a reasonable overclock value.

Step 7) Hit Freq Set and the system will be overclocked immeadiately. However, not all programs will register it, but CPU-Z and benchmarks that don't rely on processor cycles will show it.

Step 8) Reboot, and then all programs will recognize the new speeds

http://www.telusplanet.net/~sulee/DellOC.png

This procedure has worked for the Dell 400SC and a Dimension 4600. It should be no different for other Dimensions.
,,,

Sounds like a quaking bog...I aint walking into that.

Sounds like a quaking bog...I aint walking into that.

don't be a chicken.