On Tue, May 22, 2007 at 03:00:01PM -0400, Lennart Sorensen wrote: > On Tue, May 22, 2007 at 12:37:41PM -0500, Neil Gunton wrote: > > Are we talking about desktop workstations here? Forgive my ignorance, > > but what on earth requires that much RAM? Video processing? I have 1 GB > > in my desktop at the moment, and that's useful for when I'm running > > VMWare, but that's about it. Most of the time, it's just being used for > > disk cache. > > Ram is cheap, firefox leaks memory (or wastes it) like crazy. KDE > doesn't seem much better. Until people start taking code quality > seriously, it is simpler to throw more ram at it. > > > I think I must have gone to sleep for a couple of years. When I was last > > looking at Intel vs AMD, "they" were saying that AMD's architecture was > > much better than Intel's, because (I think this is right) for > > communication between cores, the AMD doesn't have to go off-chip, but > > Intel's architecture requires use of the external bus, and AMD's design > > just plain scaled better. Or something. Then fast forward to today, > > where apparently Intel's Core 2 Duo is apparently kicking the pants off > > AMD... how did this happen? Is Intel really all that much better? > > The Core 2 Duo has an internal connection between the two cores (they > are a single die) just as the Athlon 64 X2 does. The Core 2 Quad has > two Core 2 Duo dies attached together using the front side bus. So for > a quad design, the Core 2 is similar to the dual core design intel did > with the Pentium 4 (aka Pentium D). The Core 2 is based on the > Pentium-M core which goes back to the PPro (it is derived from the P6 > core). The pipeline is in the low to mid teens, unlike the netburst > which managed to go past 30 stages (great for clock frequency, bad for > dealing with conditional branches). So in terms of design, the Core 2 > has a lot more similarity with the Athlon than the Pentium 4, except it > is a bit more modern and has some clever tricks, which makes it able to > run faster than the Athlon 64 at the same clock speed. Hopefully those > improvements AMD is promising in the next version of the Athlon 64 will > in fact give them the same or hopefully better performance per clock > than the Core 2 Duo. > > > Also, I only really hear comparisons between the Core 2 Duo and Athlon. > > How about Opteron? Is the Opteron still a good choice for servers? Or > > has Xeon leapt ahead there too? > > The Opteron is an Athlon 64, except it (usually) uses registered memory > (allows more banks of memory in the server, at a slight speed penalty). > Current Xeon's are Core 2 Duo or Core 2 Quads, with a different bus > speed (I believe they tend to run 1333MHz effective bus rather than the > 1066MHz of the Core 2 desktop chips). Xeon's also usually have more > cache. Of course the opteron has the fast hypertransport link between > cpus, and per cpu memory controllers, so the memory bandwidth is better > on the opteron with lower latency, which is why the opteron still scales > better than the xeon. For single or dual cpu the xeon is usually > fastest, but for 4 or more cpus the opteron is better off since the xeon > still has to share a single bus to the chipset for all the cpus while > the opteron has the hypertransport links between cpus instead for memory > accesses and only has to use the link to the chipset for accessing > devices. Adding opterons and memory gives more overall memory > bandwidth. Adding cpus to a xeon system doesn't add bandwidth, just > processing power. Until intel some day gets an on chip memory > controller. > > > Sorry for the ignorance. I don't pay much attention to hardware stuff in > > between computer purchases. Last time I really looked was in 2005 or so. > > Lots has happened. It is nice to have some competition between AMD and > intel to keep them both going, although I like to root for AMD being the > underdog. I think it is very much horse for courses, I have seen intel dual & quad cores perform really well with some applications and I have seen AMD x2 outperform intel quad cores. The one that really stick to my mind is some testing done by a rendering house, the amd x2 outperformed the intel single, dual and quad core chips. > > -- > Len Sorensen > > > -- > To UNSUBSCRIBE, email to debian-amd64-REQUEST@lists.debian.org > with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org > >
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