If you are looking for old BIOS, floppy disk or CD support, we recommend using MemTest86 V4 which is still available for download under 'Older Versions'. Phone, E-mail, Forum Support, plus free upgrades for 12 months after purchase.ġ. The RAM address range between 640K and 1M is inaccessible due to quirks of the legacy PC memory layout (some of this RAM may be used as a shadow for BIOS ROM and for SMM, other parts may be completely inaccessible).(French / German / Czech / Polish / Russian / Spanish / Portuguese / Italian / Catalan / Japanese / Chinese) Some part of RAM is used for the System Management Mode and is not even accessible from the CPU outside of the privileged SMM code. While these RAM regions can be accessed by CPU, writing anything into them can result in unpredictable behavior. Usually the firmware (BIOS) reserves some RAM regions for its own use (e.g., ACPI tables). This code relocation is described in README.background inside the memtest86+ source code archive (the file is slightly out of date - e.g., it states that the addresses used for memtest86+ code are 0x2000 and 0x200000, but the low address as defined in the source is actually 0x10000, and the high address is either 0x2000000 or 0x300000 depending on the amount of memory in the machine).īut even with this relocation trick memtest86+ is not able to test all memory for the following reasons: However, memtest86+ is able to relocate its own code to a different address at runtime, and by using this trick it is able to test all memory which it is allowed to use by the firmware (BIOS) - just not all at once. Obviously, memtest86+ cannot test the memory region which currently contains the memtest86+ executable code (but if there are memory errors in that region, it is very likely that the test itself will crash).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |