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I guess you just run two instances of a single threaded application like Prime95 (see how hot you get!) or SuperPi. I think two instances of Prime95 will tell you whether your setup has sufficient cooling. My guess is that air cooling temperatures on overclocked processors will run through the roof.Quote:
How do you engage each core separately so you know what is running what??
Two instances of Prime....Quote:
Originally Posted by joe2004
Isn't there a little trick----make a second shortcut and then add something at the end of the executable on that shortcut-----something like that....
You also have to set something in the prefs if I remember....
Am not looking for massive overclock-----just a goal of 2.8 and am hoping for voltage around 1.55-----I use tccd and will do a low FSB/High Multi overclock so my VDIMM should be around 2.75. Looking for around 235 FSB with a 12 multi. I've been getting VERY stable results form this apparoach from San Diegos and Winnies in comparison to higher HTTs and lower multi overclocks----and while the benches are just a teeny bit slower because of RAM bandwidth-----the CPU power is the same----and the gains in stability are tremendous
My 120 x 38 Panaflo and an XP 120 HS ain't bad at all for air.....
Should be fun....
Thanks
John
Copy prime folder to somewhere... make short cut that makes it 2 prime 95 you can run.
You can set processor affinity from preference or go to task manager and set it.
As for aircooling, I am using Thermaltake Big typhoon with stock fan atm and it is easy to see 60c dual priming 1.57v @ 2.65ghz... with ambient temp of 25-27c. So, it is hotter than venice once voltage is there. (on stock though it runs even cooler than venice of same speed simply because stock vid is at 1.3v instead of 1.35 or 1.4v on venice) :P
Just download prime2004, you can select which core you want each instance to operate from or it will share if you have "no afinity" selected. I also noticed you can bring up taskmanager and select the core you want a particular app to run from if you like.Quote:
Originally Posted by johnrr6
Got my 4400+ on Saturday and I've definately got 1 duff core and one good one.
Core 0 hit 2.6GHz at 1.4v 12 hours Prime95 small FFT stable
Core 1 needed 1.57v to hit the same speed and be Prime95 stable
Core 0 is happy all the way up to 2.8GHz at 1.57v but Core 1 bombs at anything over 2.6GHz no matter what the voltage.
I'm running 2 instances of Prime95 small FFT over 24 hours (one bound to each core) to see if that will sort it.
Rilot,
I'm guessing you must be Rilot from OCuk :)
What's the stepping and week info on yours?
I've yet to test my 4400+.
Yup. That's me.
Same stepping and week as NickK so: CCBWE 0517MPMW
How do you do that exactly? I don't see that option? :confused:Quote:
Originally Posted by highoctane
Right mouse on a process, select "affinity"Quote:
Originally Posted by xgman
Anyone notice a drop in Sandra mem scores when changing form single to dual core? Seems like Sandra memory benches aren't allocatig the memory as it was on single core, loosing quite a bit of bandwitch on the test. Is there a better memory benchmark test that is appropriate for dual cores?
hmm. never saw that option. I'll have to give it a try. John asked a good question though. What if you have 6 apps open/running at one time. What happens between the cores automatically?Quote:
Originally Posted by rilot
It's cuz you went from an FX55's true 128bit memory controller to the x2's 64 bit controller ;) The FX55 will ALWAYS be faster in terms of bandwidth at the same speeds/settings.Quote:
Originally Posted by xgman
Hmm, I did not know there was that difference. I guess I've been on the FX boat for so long it didn't occur to me. I wonder how much real world difference that makes?Quote:
Originally Posted by s7e9h3n
So it's like this quote:Quote:
Originally Posted by s7e9h3n
"The one limitation that both AMD and Intel have is bandwidth. In order to maintain compatibility with present day Socket-940 and Socket-939 motherboards, AMD could not increase the pincount of their dual core processors. The benefit is that AMD's dual core CPUs will work in almost all Socket-940 and Socket-939 motherboards (more on this later), but the downside is that the memory bus remains unchanged at 128-bits wide and supports a maximum memory speed of DDR400. So, while single core Athlon 64 and Opteron CPUs get a full 6.4GB/s of memory bandwidth, today's dual core CPUs are given the same memory bandwidth to share among two cores instead of one."
However that's like saying a 3700 isn't as fast as an FX55/57 - completely ignoring the fact that the chip is dual core and the way it does things suits a different purpose better.Quote:
Originally Posted by s7e9h3n
In the end bandwidth means how fast you can get data/code to/from the memory when requested. If the FX55 is running at a multi that allows the cache to work to ensure every possible capacity of that memory bandwidth can be used then your right.
However that's dependent on the code instruction distribution.
X2 with it's limited multi doesn't use it's cache in the same way - instead the second core has the chance to get in and use the memory bandwidth. So between the cores the X2 should use more of the bandwidth - if the application is processing the same work but in a multithreaded fashion it's quite capable that the X2 will equal the FX55's use of memory bandwidth.
Single core vs. one of the X2's cores - your correct. However, as weve seen from multithreaded apps the X2 does a pretty good job of matching all but the extreme overclocked FX55/57.
Am I missing something? DC on all s939 MB's list as 128-bit.
He's taking the pish :D :pQuote:
Originally Posted by ewitte
Basically as the dual cores have a single memory bus to fight over, a simplistic statement is that it's equivilent to a pseudo 64bit memory bus.
A dual core has 128 bit access to memory. However it may have to wait for the other core's memory bus dependant operation to complete first.
Just a quick sidestep from all this ocing talk for anyone else with an X2 CPU...
Device Manager -> (your pc name) -> Computer -> xxxxxxxxx
What computer type have you got in the xxxxxx area above?
Have you got ACPI Multiprocessor or MPS Multiprocessor?
:)
I forced "ACPI Multiprocessor" so thats what shows up ;)Quote:
Originally Posted by [timko]
ACPI Multiprocessor PCQuote:
Originally Posted by [timko]
and use these
http://www.amd.com/us-en/Processors/..._13118,00.html
ACPI Multiprocessor too - using AMD's X2 driver too.
4800+ X2 in and running
Got my 4800+ X2 in my DFI rig and she fired right up....... Bios 623-3
Made 2.8 ridiculously easy at 1.42 vcore-----HTT 234 x 12 Multi
Ran two superPi's simultaneously----1 meg did 30 seconds each
Ran two Primes----Core 1 Keeps chugging along----Core 2 drops after about an hour so I'll have to tweak a bit. Temps get as high as 50C under stress and I'm on air.....I have a whole bunch more stability testing but think I'm in the ballpark with a goal of a 2.8 overclock on air....
Wasn't there a way to set memory for prime95 so they didn't share when running two instances??
This dual core stuff is a whole different ballgame.....
Ran 7 apps simultaneously and alt tabbed between them------it was instantaneous----no lag at all....
Need to test it while one core is REALLY busy with something demanding----say rendering a DVD----see how fast it switches and responds then.
Can someone explain to me how the cores respond???
When does Core 2 kick in??? At a certain percent of CPU load??? When a new application requiring a certain amount of resources starts up???
Whats the rhyme or reason a certain core would do a certain app???
In other words----can someone explain to me how the pie is divided when there are say 7 apps running????
John
John, glad you like the 4800+. If you really want to see you proc perform run the new PC Mark05. At one point it runs 5 or 6 different apps at once. PCMark is a good test for the multi-processor system.
What was stepping and date of your processor? :up:
Congrats john. I have the same questions. I'm not sure anyone other than Bill Gates knows for sure. ;)Quote:
Originally Posted by johnrr6
I don't think you can get 2x prime not to share memory. I'm also not so sure we should be all that hung up on why that 2nd instance of prime fails so much sooner than the other as long as what you really do on the computer is stable.
What stepping codes did you get?
I see, therefore the CPU where both cores are good ones will be sold under 4800 while those that have one core "faulty" will go with lesser numbers.Quote:
Originally Posted by johnrr6
Meaning you are really getting what you paid for.
AMD has this yield problems for years. Intel manufacturing of separate core makes it for the better (read lower) price but it suffers in performance.