Troubleshooting starter
- Overview of the problem
Asus A7N8X refuses to post after saving bios settings, otherwise fine.
- Full description of the problem and symptoms
I am currently unemployed and this was my best system. I was using the computer, not making any changes to it. One power up, it refused to POST. Several tries later, it POSTed. So I backed everything up and didn't shut it down for a while. After everything was backed up, tried rebooting. Would not POST.
PC will power up. Green light on MB shows power. All fans spin including CPU fan. No video, no POST.
I have a customer service email out to Asus but their 48 hour response is now turning into a full week.
Would like to get this system running again. Would prefer to avoid upgrading until my finances are back on track. Currently using an ECS K7S5A with Athlon 1.2.
- Did it work normally at one time, or has the problem always existed?
As described above, everything was working fine, no changes were being made, and the problem occurred.
- Is the problem consistent and repeatable, or entirely random, or semi-random?
Happens every time. See below.
- I already tried these steps:
See hardware list below to understand what the system should be.
Ok, here we go...
Removed current Duracell CMOS battery and checked voltage, 2.99 volts. Purchased new Rayovac battery measuring 3.13 volts and tried. Made no difference. I know that a voltmeter is not the best indicator of battery condition but I don't know what else would be better.
Verified that removing the floppy drive makes no difference so ruled that out as a problem.
Stripped the PC down to the power supply, MB, CPU, RAM, video card and floppy drive.
Removed all components from the case, cleaned, inspected and re-installed. Reseated the video card and RAM multiple times to make good contact.
Tested the Antec True 430 watt power supply with an ATX power supply tester. Tested OK. Installed a new and tested Rocketfish 550 watt PSU to see if it would make a difference. Problem still exists.
Cleared CMOS several times using the following steps:
1) PC powered down.
2) Switch on back of power supply turned off.
3) Power strip supplying monitor and PC turned off.
4) AC cable removed from back of power supply.
5) CMOS battery removed.
6) CLRTC1 jumper moved to pins 2-3 for several seconds then returned to 1-2.
7) Reverse steps 5 to 1.
PC will power up with single short beep and POST.
Presents a warning message, "CMOS checksum error - Defaults loaded"
F1 to continue or DEL to enter bios.
If I hit F1, it will continue to boot up until it gives me a boot failure message, which I expect since there are no bootable drives hooked up.
If I hit DEL, it takes me into the bios...
A) If I choose "Exit & Discard Changes", regardless if I make changes or not, the PC will reboot and POST as above.
B) If I choose "Load Setup Defaults" then "Exit & Save Changes", PC will reboot and POST without the checksum warning message and will continue to try and boot a drive.
C) Regardless if I make changes in the bios or just leave everything at default settings, if I choose "Exit & Save Changes" or if I choose "Save Changes" and then "Exit & Save Changes", the monitor will cut out, the fans will keep spinning, and that's it. It will not go any further. If I power off and then back on, the PC will not POST, lights on, fans running as before.
Further testing...
Tried clearing CMOS (2-3 jumpered) for over an hour. No difference.
Carefully popped out the bios chip, cleaned the socket and chip contacts, reseated the chip several times. Made no difference.
Cleared the CMOS, pulled out the memory and powered up.
Single long beep emitted.
I believe this to be a 'No memory detected' beep code.
- If there had been no beeps the VGA card may have had an issue.
Installed one stick of RAM, removed video card, cleared CMOS, and powered up.
One long and two short beeps, very close together, did not repeat.
Believe this to be the 'No VGA detected' beep code.
- If there had been no beeps the memory stick may have had an issue.
Repeated test with other stick of RAM, same beep results.
Left one stick of RAM installed. Hooked up the Master hard drive with Windows XP Pro.
Cleared CMOS.
Powered up. Entered bios, chose "Load Setup Defaults" then "Exit & Save Changes".
Rebooted. Hit F8 after POST. Chose Safe Mode.
Loaded Windows just fine. Slower than it should be of course.
Checking computer properties it shows the CPU as an Athlon running at 1.09 GHz.
I can reboot into Windows without trouble as long as I don't touch the bios, but I'd rather have the better performance back if possible and avoid the hassle of re-validating Windows.
What I have not ventured to try yet...
Flashing the Bios.
Since I do not understand what is failing on the motherboard I did not want to risk trying to flash the bios and having it fail, leaving me with a fully dead motherboard.
I have searched the net for a replacement Socket A board. Not much left. I would prefer to stick with this model or maybe the deluxe to make it a plug and play fix but I don't want to invest much into it.
So any ideas as to what is happening? What do you all suggest?
- My software:
Doesn't really matter but...- Operating System and service-pack level: Windows XP Pro, SP3
- Antivirus: Avira AntiVir Personal Free
- Firewall: Comodo
- Not a software issue...
- My hardware
- Home-built System
- Case: Antec SX835II, Performance II Series, Workstation Tower
- Motherboard: Asus A7N8X rev 2.00, Bios version 1010
- CPU model: Athlon XP 2500+
- CPU cooler: Thermaltake Silent Boost
- Video card(s): ATI AIW 8500
- RAM: Mushkin DDR3500 Level II 991098, 512MB x 2 stick kit
- Power supply: Antec True 430 watt max AND Rocketfish RF-550WPS 550 watt max
- Case Fans: 2 original Antec 80mms in the back, 3 PanaFlows in the front
- Home-built System
- Other information that might be relevant
Motherboard looks good without checking it out chip by chip. Has not been abused. Was mildly overclocked to around 180 FSB but temps were always low.