2010/1/17 Jean Francois Martinez <jfm512@xxxxxxx>: > I fail to understand how manipulating 16 bit values can benefit of > 64 bits instead of 32. I still think it is the 16 registers and thus > far less restrictive than "large chunks of data processed 64 bits at a > time" Depends on the operation at hand. If you need to do an XOR across a block of data then if you can do that in 64bit chunks instead of 32bit chucks, or even 16bit ones, then 64bit will win hands down. Also, many 64bit CPUs also have the capability to load four 16bit or two 32bit values into a 64bit register, then perform an operation on each value in one step. Again, a clear advantage for 64bit. >> But all that is beside the point. The original query was about >> drivers that were clearly broken in the 64bit version but potentially >> OK in the 32bit version and not whether 64bit was better than 32bit. >> That's why I suggested using the 32bit version as a workaround, >> ideally using a Live CD before re-installating in case it was broken >> as well, and wait for the bugs to be squished. > > Ok, but later you told that 64 bits brought nothing for people who had > less than 4Gs of RAM No, I said that 64bit offered advantages if you have more than 2GB or RAM, although Alan set the bar much lower - at 960MB or so. That's not the same thing as saying that 64bit doesn't offer any advantages if you have less than 2GB. Again, for the record, I'm with Alan on this - you should generally choose 64bit over 32bit every time - but I'd also add the the following 3 exceptions: Your hardware doesn't support it (32bit CPU) Your main applications run faster in 32bit mode (per Jerry's post) The 64bit version has known issues (like Enrico's drivers) My original recommendation to Enrico was that if moving to 32bit sorted out his 64bit driver woes, then he should do that and wait for the 64bit versions to be fixed. Unless Enrico has the skill and time to fire up a debugger and fix the problem himself, then it's better to be productive in 32bit mode than suffer problems in 64bit mode. If you look at my original post on this thread, the second paragraph that seems to resulted in us going off on a tangent is aimed at the case of a *general purpose PC* - ie. something that spends a lot of its time idling and waiting for the user to input data, and even then I said "most of the time". I specifically excluded situations involving addressing large amounts of memory (>2GB) or spending a lot of time processing the kinds of data that see the biggest gains from 64bit from that. -- Andy The only person to have all his work done by Friday was Robinson Crusoe -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
