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| Thread ID: 79445 | 2007-05-20 10:08:00 | Machine_check_exception | pctek (84) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 551409 | 2007-05-21 04:19:00 | Memtest it shows the amount of RAM being tested is lower (by only 1MB or so...) Er.........but I meant it shows this on the POST screen. |
pctek (84) | ||
| 551410 | 2007-05-21 05:29:00 | Er.........but I meant it shows this on the POST screen. Yes, I know, mine does too, I was using Memtest as an example :rolleyes: | The_End_Of_Reality (334) | ||
| 551411 | 2007-05-23 04:11:00 | It is sensible to not "test" the bottom 1MB of memory in the boot sequence. The BIOS is ROM; some of the 1M space might not be there, so looking for it would be disastrous. The memory sizing operation checks whether each memory block is present by writing to a location at the start of the block and reading it back. If the value is the same, it steps to the next block. If it doesn't get the same value back, it stops. That might make your GBs of memory be reported as 1MB, or less. :D | Graham L (2) | ||
| 551412 | 2007-05-23 07:41:00 | It is sensible to not "test" the bottom 1MB of memory in the boot sequence. The BIOS is ROM; some of the 1M space might not be there, so looking for it would be disastrous. ? Not there? Where is it then? Anyway, my graphics card has been replaced and the new one is on the way back to me. So I guess it was graphics..................Morningstars techs are pretty thorough. |
pctek (84) | ||
| 551413 | 2007-05-23 07:51:00 | Remember that the lowest 1 MB of address space is that specified for the IBM PC in 1982. The BIOS is at the top of that. There's space allocated below that where extra ROM BIOS extensions can be put (E000 for VGA video?), other space for NICs, and RAM starts at 0:0 and goes up from there. So there will usually be holes where no memory exists. The early AT POST would count up from 0:0, report conventional memory, then look for any extended memory and report that. I don't know what you would see if you managed to put 640 kB of memory on a new motherboard: maybe the POST would report that much. But I'd guess it would say there was none. If there are GBs or lots of MBs, it's easiest for the sizing routine to just ignore the lowest 1 MB of address space. With 1GB that's 0.1%. ;) And, I'll repeat, it's not a memory "test". It's just a check for presence of r/w memory. |
Graham L (2) | ||
| 551414 | 2007-05-23 21:17:00 | And, I'll repeat, it's not a memory "test". It's just a check for presence of r/w memory. Its interesting because this doesn't show on my neighbours PC, its just reports the lot. And a customers old HP which had another PC133 256mb added to it, would report a total of 370. Until I replaced the faulty module. |
pctek (84) | ||
| 551415 | 2007-05-24 05:47:00 | Maybe some BIOS coders are honest. ;) That first megabyte is almost certainly not used by Windows, because any RAM in the high end is overlaid by the ROM containing the BIOS code. The very low end is probably still used by the BIOS tables for DOS. Look at what's in 0040:0000 and up from there for the COM: and LPT addresses. They're probably still put there. ;) | Graham L (2) | ||
| 551416 | 2007-05-24 07:49:00 | Well I've had a lot of weirdness here in the last week. We had some friends down from Auckland and the following occurred during their stay: BSOD - Graphics card, as I have already said, probable cause the dodgy PSU I had in before. Dishwasher flooded. It has always leaked a tiny bit, this was a full flood. Only did it the once. No reason we could see. Dryer decided to not heat, just spin cold. Only the once. Next day it was fine. TV, DVD, Sky, heater all plugged into multipower thingy. The lot shut off. No, there wasn't an overload cutout on the power thing. All other electrics in house fine. PC was running in another room OK. Circuit breaker fine. As we stood pondering, it all came back on. They departed, leaving us with a Rhinovirus and some appliance paranoia. |
pctek (84) | ||
| 551417 | 2007-05-24 08:00:00 | Just wait until you reap the full benefits of the IP6 extended IP addressing scheme when every electrical device has its own IP address, and can be managed and have its software automatically updared through the Internet. (Of course, to have an Internet address, every device will have to have a computer, and an OS ... even a manual toothbrush). This will obviously be a very profitable state of affairs, so there's really only one corporation in the world with the experience and skills necessary to provide the software and manage things like bugs and security patches in a totally reliable, errorfree, and, most important of all, secure way. When needed, I'm sure Bill will volunteer to do it. |
Graham L (2) | ||
| 551418 | 2007-05-24 09:31:00 | Spheres of discontinuity (SoD) float through the Universe, sometimes they are small (as a dishwasher) other times they are larger than the Earth. A Sod cause all the known laws of Physics to temporarily be invalid and confusion rules, the condition is not permanent. | zqwerty (97) | ||
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