Nikos Chantziaras wrote: > On 06/12/2018 11:27, Dale wrote: >> >> I've bought but not yet installed a FX-8350 CPU. I have this in my >> make.conf file: >> >> CFLAGS="-march=native -O2 -pipe" >> USE_CPU=" > > USE_CPU does not do anything, AFAICT. CPU features are specified in > CPU_FLAGS_X86. You can get appropriate flags using the > app-portage/cpuid2cpuflags tool. For example, here: > > $ cpuid2cpuflags > CPU_FLAGS_X86: aes avx mmx mmxext pclmul popcnt sse sse2 sse3 sse4_1 > sse4_2 ssse3 > > So in my make.conf, I use: > > CPU_FLAGS_X86="aes avx mmx mmxext pclmul popcnt sse sse2 sse3 sse4_1 > sse4_2 ssse3" > >
I was wondering if those are used anymore. I did that a looooong time ago. Things change. After I do the swap, I'll get the settings up to date. No need changing things now just to change them again later. Besides, the current settings may be better when I install the new one. I did have the correct one in make.conf but didn't notice it to post. I did comment out the old unused one tho. The current setting is this: CPU_FLAGS_X86="3dnow 3dnowext mmx mmxext popcnt sse sse2 sse3 sse4a" I'll update that when I get the new CPU installed. I already have cpuid2cpuflags installed. At least now I know it is the current tool to use. ;-) I wish the monthly news letter would come back to let us know about some of these changes. Some things don't require a news item but we still need to know when we can remove outdated stuff and add new stuff. >> Those were put there ages ago, likely when I built and installed Gentoo >> on this rig. Do I need to change those to something that is compatible >> with both CPUs and then change to the new CPU after it is installed? Or >> will the new CPU be close enough that it won't matter? Right now, I >> don't know for sure what the new CPU supports or doesn't. > > Just install the new CPU and run cpuid2cpuflags to see what to put in > CPU_FLAGS_X86. You can delete USE_CPU as that doesn't seem to be used > for anything. > > Old setting gone. > >> While at it, going from a 4 core CPU at 3.2GHz to a 8 core CPU at >> 4.0/4.2GHz, just how much increase can I expect? Will it double and >> that's about it or will it be more than that? > > You won't get anything close to double the speed. The extra cores will > mostly go unused, unless you use applications that make use of them. > > You will still get a speed up due to the newer CPU architecture and > the higher frequency. > > What I was thinking about is something like when compiling and all the cores are used. In other words, CPU is at max load. Right now, I have only 4 cores. New CPU doubles that and each core is faster as well. As a example, Firefox takes about a hour to compile. I was hopeful that would drop to 30 or 35 minutes or so. I realize there is some overhead on this so it isn't a exact thing. I was just curious about a rough number to expect. I know upgrading from 16GBs of ram to 32GBs has helped. I tested Dolphin the other day and it still have its memory hog issue. At least this time I had enough memory that it didn't cause a crash. ;-) >> Also, since it has two >> speeds, will it run at the slower or faster one? Will it depend on >> load? I've never had a CPU with two clock speeds like this before. > > The two speeds specify the lower and upper speeds, depending on how > many CPU cores are currently being under load, and also how much load > there is. You don't have to worry about it though. It's all automatic. > When you're not running anything that stressed the CPU, clock speeds > are actually lower than 4GHz (some CPUs can clock down to 1GHz or so > when they're idle and not doing anything.) Once something CPU-heavy > runs, it will clock up to 4.2GHz. If you run something that stresses > all CPU cores, then it will go to 4.0GHz to avoid overheating. > > But again, all this is automatic. > > > That's good to know. That I was wondering about and couldn't find a clear answer on. I didn't know if I needed to install something to manage that or what. At least now I know to install the CPU and it will do its own thing without me having to worry about it. BTW, I know my video card does that too. The processor on it varies its clock speed by a fairly wide margin. Speaking of, I also found a MSI GeForce GTX 650 1GB Video Card. It is a used card but it is faster I think than my current 220 series. Keep in mind, my idea of gaming is Kpatience. The biggest load is watching TV. ;-) Thanks for the info. This answers a lot of questions I had. Makes me hopeful that this will work like I expect. Dale :-) :-)
