Prime 95 help

How do i run 2 primes so i can test if my pc is stable

To test the stability of overclocked CPU:

Double click on PRIME95.EXE to start the program.

Just Stress Testing (if prompted) > OK >
Options > Torture Test > Blend


The program should not give any errors.
It may be necessery to run the program 12-24 hours to make sure an overclocked system is stable (no program errors displayed).


If you get errors only after several hours, this is a result of slight instability because the system is running with little or no margin. It's stable enough to boot and to be moderately stressed, but as soon as the system is under enough load to go over that critical point, it will freeze. To be 100% stable, Prime95 should run 12-24 hours without any errors.

The whole point of testing is to see if you get errors or not thus testing the stability. The meaning of errors themselves is not the issue.

he wants to know how to run 2 instances of prime95?? =d on the same computer? hehe

Make a copy of the Prime95 folder and then launch from there.

Why do you want to run 2 copies at once, Prime95 is stressing your CPU by 100% usage, 2 times Prime95 would also just make 100% usage of your CPU, means just one Prime95 running is enough

Maybe he's running a hyperthreaded CPU and wants to load it 100% instead of just 50%.

Here:

-Open the Prime console as you normally would, but don't start the torture test.

-Then go to Start button - Run.

-Click the browse button and find where you located Prime95.exe Once you find it, click Open.

- The path in the browse box will probably look like this "C:\Program Files\Prime95\Prime95.exe"

- Put your cursor at the end of that text line after the ...exe"

- Press the space key once and then type -A1 (dash A one)
"C:\Program Files\Prime95\Prime95.exe" -A1

- Press the OK button.
----------------------------------------------

You now have two Prime Consoles

Now before you begin the tourture test, go to Options - CPU and in the two boxes for amount of memory used, take whatever number shows in there now and divide it in half, and then enter the new halved number in both boxes. Save and exit the options box. Do the same thing for the other Prime console. Failing to do this will result in the chewing up of your paging file (I know cuz I just tried LOL )

Now run Torutre Test on both consoles.....

You're now using 100% CPU Utilization on an HT CPU.

Ralf Hutter said:

Maybe he's running a hyperthreaded CPU and wants to load it 100% instead of just 50%.

Click to expand...

I've said it before and I'll say it again: a single instance of Prime uses 95+% of the CPU resources available to it. It's Windows that says it's only using 50% because tskmgr doesn't know the difference between virtual processors and physical processors.


If you want to run two instances of Prime as a stress test, R.H.'s method above works fine. However, I would recommend giving one instance ~85% of your system memory and having it run blend, then give the other instance 10 megs or so and have it run small FFTs. This puts the most stress on the CPU, while still providing adequate coverage for the memory and chipset.

Yes iam using a ht proc its a 2.4c anyways the 2 boxes both had 8 i did what u said divied it and put 4 in there spots but then it gives me this error

Please enter a intagear between 8 and 459

I agree with NookieN, If you want to run two instances set the Ram to 85% of your system memory in one console and 10% in the other....You should have much more than 8Mb right?

yah i have 512

why -A1 does this work with all programs to run 2 instances of it? hmm

No, I think the -A1 tells Prime to use a different set of .ini files for each instance. Most of the config data for Prime95 is stored in local.ini and worktodo.ini. If you were actually participating in GIMPS, two copies of Prime would not be able to share the same ini files.

Most programs will let you run multiple instances. If you have a dual processor machine, you can restrict which CPU each gets to run on with the set affinity option in task manager.