BIOS Updates forum

The above board is in a PC which was working fine until I put it on the shelf for about 5 months. I tried to boot it up again today, and there isn't a kick in it - there is no POST. I tried undoing all power connections and a few other things, but no go. Is it possible that the period of non-use means that the CMOS battery has run down? If so, what is the best way to recover from this once I get a new battery?

Thanks

Kevin

Possible but I haven't seen a bad CMOS battery result in no POST.

Hmm. Wonder what it could be then? I suppose the video (which is integrated) and the membory might be the next suspects.

try a fresh cmos battery first, it is the cheapest option to replace.

I tried a new CMOS battery, but it made no difference. It turned out to be a faulty memory stick. With both good and bad sticks in, there were no error beeps, but with only the bad one in, I got beeps signifying that no memory was available.

hmmm, interesting find. thanks for sharing that info with us.

Yes, I found it counter-intuitive. You would think that if one stick was faulty, it would just boot on the good one (which was in fact in the first memory slot), and you would see that half your memory had disappeared. Or alternatively, if it didn't like booting with half its memory, that you would get some sort of beep to tell you that your memory has gone down the swanee. But doing *neither*, and just sitting there, is odd!

It would be nice if the system would just ignore a faulty stick of memory, but to the best of my knowledge any bad hardware can cause system instability.

Windows at times probably tries to take advantage of as much memory as it can get to increase it's performance and decrease use of the swap file. If you have 2 * 128MB sticks for example, then as soon as the second one is accessed, then if the second one is faulty you will start experiencing problems.

Also, RAM probably suffers from some data fragmentation issues similar to that of disks, except that they are only an issue until the next reboot when the RAM is cleared. Therefore if an O/S does not clean up after itself properly, 150MB may be in use when unused bits of memory mean that only 120MB needs to be, meaning that the system starts taking advtange the second of two 128MB sticks when only 1 stick needs to be in use.

Ritchie wrote:Possible but I haven't seen a bad CMOS battery result in no POST.

I have. Unusual but possible, especially on older 386/486 boards with a rechargeable NiCd CMOS battery.

At least one HP Vectra 486 uses a CMOS back-up 1 farad capacitor and the machine won't start until it is charged enough - leave the machine unplugged from the mains for a fortnight and you have a "dead" machine when you come back.

I have a 286 board that had NiCd battery. It initialized the video card and displayed a message: "CMOS INOPERATIVE. SYSTEM HALTED." The battery was shorted so I desoldered it - and the board works.