Changed cpu multiplier from 17 to 19 now have blank screen on foxconn a88gmx, cant reset as cannot access bios

check the capacitors behind the processor and the heat-sink,some of them are faulty......

845 mother reaper layout digram

The BIOS. Overclocking is best done in the computer's BIOS (Basic Input/Output System or Binary Integrated Operating System). There are also some motherboards that let you do a basic increase in power by setting a jumper, but this is dangerous and you have no real stability control.

There are some software programs available which allow you to overclock inside the operating system, but the best results are achieved by changing BIOS settings. Usually you can get into your BIOS by pressing DEL (some systems may use F2, F10, or Ctrl-Enter) as soon as your computer begins the POST

(Power On Self Test - when it shows the RAM size, processor speed, etc.).

Here, you can change your FSB (front side bus), memory timings, and your CPU multiplier (also referred to as CPU Clock Ratio).

Clearing your CMOS. Sometimes, an overclock can become unstable. If this happens, or your computer will not boot, you will need to reset the BIOS back to default and start over again.

This is done by clearing the CMOS (a small piece of memory on the motherboard which stores your BIOS configuration, and is powered by a small battery). Some newer motherboards will bypass user settings in the CMOS if the computer fails POST (often caused by a faulty overclock). However, most motherboards require a manual clear.

This can be done in two ways, depending on your motherboard. The first way is by changing the position of the clear CMOS jumper on your motherboard, waiting a few minutes, then repositioning the jumper to its original place.

The CMOS Jumper

The second way, if your motherboard doesn't have this jumper, consists of unplugging your computer, removing the little CMOS battery, then pressing the power button (your capacitors will discharge), and waiting a couple of minutes.

Then you have to refit the battery and plug in your computer. Once your CMOS is cleared, all BIOS settings are reset back to default and you'll have to start the overclocking process all over again. Just so you know, this step is only necessary if your overclock becomes unstable.

Locked or Unlocked. The first thing to know when you start the process of overclocking, is whether your processor is multiplier locked or unlocked.

To check whether your CPU is locked, lower your multiplier via the BIOS one step, for example from 11 to 10.5. Save and exit your BIOS and your computer will restart.

If your computer posts again and shows the new CPU speed, it means your CPU is unlocked. However, if your computer failed to post (screen remains black) or no CPU speed change is present, this means your multiplier is locked

Multiplier Unlocked Processors. Usually, your max overclock is limited by your memory, or RAM. A good starting place is to find the top memory bus speed in which your memory can handle while keeping it in sync with the FSB. To check this, lower your CPU multiplier some steps (from 11 to 9, for example) and increase your FSB a few notches (e.g.: 200 MHz to 205 MHz).

After this, save and exit your BIOS. There are a few ways to test for stability.

If you make it into Windows, that is a good start. You can try running a few CPU / RAM intensive programs to stress these components. Some good examples are SiSoft Sandra, Prime95, Orthos, 3DMark 2006 and Folding@Home.

You may also choose to run a program outside of Windows, such as Memtest. Load a copy of Memtest onto a bootable floppy, then insert the disk after you have exited the BIOS.

Continue to increase your FSB until Memtest starts reporting errors. When this happens, you can try to increase the voltage supplied to your memory.

Do note that increasing voltages may shorten the life span of your memory. Also, another option is to loosen the timings on the memory (more on this a bit later). The previous FSB setting before the error will be your max FSB. Your max FSB will fully depend on what memory you have installed. Quality, name-brand memory will work best for overclocking.

Now that you know your max FSB, you'll figure out your max multiplier. Keeping your FSB @ stock, you raise your multiplier one step at a time. Each time you restart, check for system stability. As mentioned above, one good way to do this is by running Prime95.

If it doesn't post (reread the section about clearing the CMOS), or Prime 95 fails, you can try to raise the core voltage a bit. Increasing it may or may not increase stability. On the other hand, the temperature will also be increased. If you are going to increase the core voltage, you should keep an eye on temperatures, at least for a few minutes.

Also note that increasing voltages may shorten the life span of your CPU, not to mention void your warranty. When your computer is no longer stable at a given multiplier setting, lower your multiplier one step and take that as your max multiplier.

Now that you have your max FSB speed and your max multiplier, you can play around and determine the best settings for your system. Do note that having a higher FSB overclock as opposed to a higher multiplier will have a greater impact on overall system performance.

http://www.pcadvisor.co.uk/news/index.cfm?newsid=107977

hope this helps

The only way to reset the BIOS is to take the laptop appart, remove the CMOS battery and short the reset jumper on the motherboard. Unfortunately this is unrealistic unless you are handy with taking things appart and putting them back together.

Let me know if you have any questions.

blank screen a lot of cause.

firs chek the os is available,,. check the ram, cpu, of board.. vga,,

try to reset cmos by removing CMOS battery from motherboard and reinsert again...

Try clearing the CMOS (CMOS reset)...and restoring defualt bios

You could check inside your BIOS setup for it could be disabled.

1. Try change PSU - 350-400Wt is recommended as minimum.
2. Try update BIOS to last version.