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Solve : Infinite Reboot Cycle? |
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Answer» So, here's the story. A few weeks back, I had posted on the forums that my computer was not booting. I got some help from someone, who asked me to follow up. Unfortunately, I came down with an illness which caused me to lose my memory, so I can't remember what my forum name was and I neglected to respond to him until someone reminded me. Your hard drive is not being detected in the BIOS... Quote Drive 0 not found: Serial ATA, SATA-0 That's because it was unplugged. Of course it wouldn't be detected... But, just in case you were onto something, I'm not going to let my sarcastic nature get in the way. I disconnected everything except for the drive and a stick of RAM (tried 3 different sticks in all of the slots) because apparently it won't boot without RAM. It would give the "RAM error" beep message when it tried to post. Instead of the error before, I got this: Quote Drive 4 not found: Parallel ATA, PATA-0 (PRI IDE Master) Connecting a keyboard produced the same result, and I was unable to press F1 or F2 (obviously). That "Strike F1 or F2" message is incredibly stupid. Oh, and I forgot to mention, on every reboot it makes 2 short beeps.The PS/2 port for your keyboard may be no longer working off your motherboard. Check your keyboard status in Device Manager for any yellow exclamation marks. Expand + Keyboards and right click on properties then resources and check for to see if you have any conflicts. Try the troubleshooter as well. The PS/2 port will sometimes fail and won't give any indication of failure in Device Manager, so be aware of this. Try a USB keyboard to eliminate the PS/2 port as a source of problems if you haven't done so already. Quote from: Karnac on March 31, 2009, 05:58:04 PM The PS/2 port for your keyboard may be no longer working off your motherboard. Ehehe. It won't boot. In fact, even reinstalling windows won't work, or running memtest. It simply reboots before it gets to memtest, diagnostics, installing a new OS or booting windows. Neither USB or PS/2 keyboards work, and I tried the built-in USB slots and an external USB card. I wish it would be that easy to just look in device manager. Is it possible a faulty PS/2 port could cause the system to auto-reboot? Although, booting into the BIOS itself does work, but I still can't use a keyboard. Thus I can't check any of the settings.Can you get into safe mode?.... if you can then try Start> accessories>accessability> on screen Keyboard......Nope, just a reboot after it finishes loading all the drivers.BaRR, I did find this....."If you replace the keyboard with another, or if the original keyboard is tested on another PC and it works there, this implicates either the keyboard controller chip or the motherboard itself." http://www.pcguide.com/ts/x/comp/kb_Failure.htmBaRR, have you tried to get into the bios by tapping the delete key at boot up. If you can get into the bios and look at the settings for drive detection, you may be able to reset there, to boot using the CD first and insert the windows disk (if you have one) and boot from it. I have had keyboard failure messages in the past and yet never had a keyboard failure as the end result. (That doesnt mean of course that it isnt your issue). Mostly Ive found the problem is the bios or O/S. (maybe worth looking into?) Quote from: Karnac on March 31, 2009, 07:11:16 PM BaRR, Keyboard Controller Chip, that helps very much, thanks. now where can I get one of these? Quote I have had keyboard failure messages in the past and yet never had a keyboard failure as the end result. That usually happens when you have a key pressed down on your keyboard when you boot.the keyboard controller is in charge of the A20 line access to high memory... coincidentally, memtest and windows both access High memory through the default A20 handler before replacing it with it's own. if possible, try to get into your CMOS setup and try toggling a "A20 fast gate" option, or something similar, if present. Yes it's a stupid architecture. the keyboard controller should be for- you know, the keyboard. but apparently those FOLKS at IBM decided otherwise, and now we're stuck with the legacy.Hmm...two short beeps......memory error ties into what BC has posted....maybe clean and reseat the memory or replace with good known chips wouldn't be a bad idea.I will explain further, to satiate people curiousity the A20 line relays the 20th bit of the address line. This was introduced with the 286 processor, which could access more then 1MB of RAM. however- the 8088 and 8086 processors could only access 1MB of ram and thus only used 20 bits for their address lines. Unfortunately programmers had used the fact that their were only 20 address lines in ORDER to perform clever tricks, since accessing an address higher wraps around to 0. With the advent of the 286 and more then 1MB of RAM, it w imperative that there be more address lines for representing these memory addresses, so they added extra gates, including the A20 line. Now, the curious part of this is that previous to the 286 the keyboard controller was at the exact address that now contained the A20 line. So they retrofitted an A20 gate into that address along with the keyboard controller. A Frankenstein task if I ever saw one. And now- on to something relevant: Quote Enabling the Gate-A20 line is one of the first steps a protected mode X86 operating system does in the bootup process, often before control has been passed onto the kernel from the bootstrap (in the case of Linux, for example). which explains almost all behaviour that has been reported; memtest does it as well. prognosis? Failing other suggestions- it could be a shot motherboard. That sounds like it fits my problem exactly, especially the crashing directly when it should be loading the keyboard. Is there any way to replace only this module, or do I need to find a motherboard that is 2-3 years old? I'm not throwing the whole computer out, it's a little slower but smoother running than some of the new ones, and quieter too. Definitely not getting trashed. Anyway, I digress... Do I need to get a new motherboard or can the "A20 Line" be replaced on its own? Also, if possible, could you instruct me how to get into the CMOS? Future reference would be much appreciated.I don't believe you can replace the part; it's integrated into the chipset, and even if it wasn't, you would need some soldering skills... I could be completely wrong; as previously stated, all of this could easily come about from memory errors. Now- just to reiterate: are you using a USB or a PS/2 keyboard? have you tied alternating? Did you enable "legacy USB" in the CMOS? (accessed usually via F2,Del, or some other key at boot) |
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