After numerous posts resulting in people asking how long, what to use, how to use it etc I thought it might be a good idea to post up a little guide on this subject of 'stability' rather than the great (if a little outdated now) overclocking guide here .
Before you begin
Is a good idea to stop running any background tasks that could interfere with the tests. You want the stability programs to use 100% of the cpu cycles to fully test them so things such as virus scanners that may run can take away some of the cycles and therefore possibly cause an error. I simply start my chosen test and leave it to run overnight without interuption from myself. It is possible to set priority in certain programs and this is also a good idea aslong as the priority isn't so high that when you return to the PC you can no longer get it to respond. A priority of 8 or 'high' is quite adequate and I would advise against 10 or 'realtime' for the above reasons. IT is possible on some machines to carry on doing simple tasks while stress testing such as surfing the net etc but I would strongly advise against running your fave game while testing for stability.
It is also usefull to run spyware checks and a quick virus check to ensure your PC is running smoothly with no unknown nasty background tasks running (its good practice to do this often anyway!).
1. Applications required
Firstly before you start overclocking I would definately recommend the use of some kind of temperature monitoring software. Here are a couple of popular examples but there is usually one that will come with your motherboard driver disk.
Motherboard Monitor
Speedfan
Its also usefull to use CPU-Z as this will give you basic information of your CPU and memory speed, Vcore aswell as motherboard revision.
CPU-Z
Once you have those setup and you are well into your overclocking then you are going to have to test for stability.
Memtest86(+)
This small program will test memory and will throw up any faults your memory has.
30 passes test 5, 30 passes of test 8 for a quick test (2 hours roughly).
Then 8-10 hours overnight full test. - smids
Super PI
This modded version of super PI will calculate in milliseconds and is a VERY basic (but quick) test of stability. This program will also give an indication of how fast your setup is compared to others and is ideal to see what effects different memory tweaks have.
Prime 95
Few applications will test your CPU more thoroughly than Prime 95. Put in very basic terms, Prime 95 will test your CPU's ability to use arithmatic correctly. Any incorrect calculation will result in a 'failed test' ergo instability.
There are many more stability testing applications (the new version of SP2004 to name a good one) available but I find those mentioned are as good a test as any in finding CPU/memory instability without the bells and whistles of other programs.
Other Applications not needed in this guide but usefull nonetheless:
SP2004 Orthos
The latest version of SP2004. This version is much improved as it tests both cores but only uses one program so there is no need to create separate folders like in P95 or use two versions of the same program such as SP2004. I'm still playing with this and have so far found that it isn't as sensitive to failures(memory related) as P95 but it certainly looks the business.
SP2004
Very similar to Prime 95 with a neater GUI interface. There are reports however that Prime95 will throw up errors that SP2004 dosn't catch (even though they are in effect the same program.
Everest
A very thorough program that will give you various info on things such as memory bandwidth/timings and CPU settings and temperatures. This tool can also be used to find out any conflicts your PC may have with 'performance tune up'.
S&M
If you want to see your CPU to reach its max temp under current cooling conditions then this program will do it for you and also stress you PC's other main components. This program is ideal for burning in a processor as you can set it to loop certain tests and it will not stop if it fails although it will tell you it has failed. - A perfect overnight stressor!
2. Installation (Dual core)
Most of the above programs are relatively easy to setup and use, just point and click. For Dual core users though a little extra is required for SuperPI and Prime 95.
For either of these programs to be run successfully and be used as a 'true' representation of stability in a dual core environment TWO versions need to be running simultaneously as you have in effect TWO CPU's (or rather two cores) . To do this and to prevent unexpected errors you will need to run the two .exe's from separate directories.
Super PI
1. Extract the downloaded SuperPI mod.exe to the desktop (right click - extract - desktop).
2. Create two 'new folders'
3. Rename Folders (for simplicity SPI 1 + SPI 2)
4. Create a copy of the SuperPI mod.exe and paste it into SPI 1 folder
5. Cut and Paste the remaining SuperPI mod.exe into SPI 2 folder
You now have 2 separate .exe's of SuperPI which will not clutter your desktop should you get errors.
Prime 95
1. Install the program
2. Create 2 folders on the desktop and rename to Core 0 and core 1
3. Find the Prime95.exe (default: C:\Program Files\Prime95).
4. Copy 1 version of Prime95.exe into Core 0 folder and copy another version into Core 1 folder.
You now have 2 separate .exe's of Prime95 which will not clutter your desktop should you get errors.
3. Setup Prime 95
1. Start Prime95 (for dual core start from core 0 folder)
2.When the initial screen pops up (join GIMPS / Just stress testing) click on 'just stress testing.
3. (dual core) Click on advanced then affinity
4. (dual core) Uncheck the 'let program run on any CPU' box
5. (dual core) Set the 'Specific CPU to run on 0
6. (dual core) Start other version of Prime 95 (core 1 folder) and apply steps 3-5 but this time set it to run on CPU 1
7. Click OK
8. Now go to Options and click torture test
Now we need to decide which test to run. AFAIK the tests run like this:
small fft - CPU
large fft - CPU+Memory controller
Blend - A blend of above but with lots of physical memory used
For now we will stick with small fft so...
9. Check small fft and click ok (dual core users obviously need to do this for each instance of Prime95)
This will start a looping test (on each core). This test will run indefinately or until you stop it or it produces and error.
Dual core uses should see 100% usage on each core(which shows as 50%+50%=100%) while this test is running (press CTRL+ALT+DEL > Performance tab). It makes no difference to set affinity of prime 95 in the traditional way process(rightclik process>set affintiy) as the application is controlled by prime and not windows although it dosn't hurt to do that if you so wish.
4. Testing stability
This is a highly debated topic and one I do not claim to be an 'expert' on. I will give you my opinion on the quickest way to test for stability but please don't flame me.
1. The quickest half decent test is to run 1m of super PI as this will only take 30 secounds and will throw up an error if your stability is way off. If it dosn't pass 1m superPI you will need to check your overclocked settings and/or memory timings as this is by far the easiest test to pass.
2. If you pass SuperPI 1mb then go on to do a 32m pass which will take around 30 minutes to complete and will stress your CPU and memory for longer. A 32m pass is a fair indication of stability although not a TRUE indication of a stable system imo. For that you will need Prime 95.
3. If SuperPI has passed without problems then you can go onto Prime95. This is where it becomes tricky so I suggest sticking to the 'overclocking guide' and testing each individual component seperately to give an indication of where the problem in stability lies. For 'extreme' stability that is required for folding etc then a minimum 24hr pass on all three tests (small,large and blend) 'should' be sufficient although I have had a cpu that failed prime after 32 hours! I would call that stable enough tbh. For the average joe who uses his PC for a majority of tasks(gaming,encoding etc) I would suggest a 12hr pass minimum.
Many people report that they have failed prime instantly and yet continue to use there PC's without a hitch. Well all I can say is good luck to them. Personally I like to know that my PC is stable and if an error is thrown out by Prime then your PC is not stable PERIOD. It has made a calculation error and errors like that lead to instability, BSOD and worst of all hard drive corruption resulting in loss of data and probable scrambled OS installation which means a reinstall. I would rather clock 100mhz less and have stability than risk a lengthy reinstall and all the associated hassle that goes with it.
Hope this is helpful to a few people and prevents the NUMEROUS stability questions regarding P95/SuperPI.
Before you begin
Is a good idea to stop running any background tasks that could interfere with the tests. You want the stability programs to use 100% of the cpu cycles to fully test them so things such as virus scanners that may run can take away some of the cycles and therefore possibly cause an error. I simply start my chosen test and leave it to run overnight without interuption from myself. It is possible to set priority in certain programs and this is also a good idea aslong as the priority isn't so high that when you return to the PC you can no longer get it to respond. A priority of 8 or 'high' is quite adequate and I would advise against 10 or 'realtime' for the above reasons. IT is possible on some machines to carry on doing simple tasks while stress testing such as surfing the net etc but I would strongly advise against running your fave game while testing for stability.
It is also usefull to run spyware checks and a quick virus check to ensure your PC is running smoothly with no unknown nasty background tasks running (its good practice to do this often anyway!).
1. Applications required
Firstly before you start overclocking I would definately recommend the use of some kind of temperature monitoring software. Here are a couple of popular examples but there is usually one that will come with your motherboard driver disk.
Motherboard Monitor
Speedfan
Its also usefull to use CPU-Z as this will give you basic information of your CPU and memory speed, Vcore aswell as motherboard revision.
CPU-Z
Once you have those setup and you are well into your overclocking then you are going to have to test for stability.
Memtest86(+)
This small program will test memory and will throw up any faults your memory has.
30 passes test 5, 30 passes of test 8 for a quick test (2 hours roughly).
Then 8-10 hours overnight full test. - smids
Super PI
This modded version of super PI will calculate in milliseconds and is a VERY basic (but quick) test of stability. This program will also give an indication of how fast your setup is compared to others and is ideal to see what effects different memory tweaks have.
Prime 95
Few applications will test your CPU more thoroughly than Prime 95. Put in very basic terms, Prime 95 will test your CPU's ability to use arithmatic correctly. Any incorrect calculation will result in a 'failed test' ergo instability.
There are many more stability testing applications (the new version of SP2004 to name a good one) available but I find those mentioned are as good a test as any in finding CPU/memory instability without the bells and whistles of other programs.
Other Applications not needed in this guide but usefull nonetheless:
SP2004 Orthos
The latest version of SP2004. This version is much improved as it tests both cores but only uses one program so there is no need to create separate folders like in P95 or use two versions of the same program such as SP2004. I'm still playing with this and have so far found that it isn't as sensitive to failures(memory related) as P95 but it certainly looks the business.
SP2004
Very similar to Prime 95 with a neater GUI interface. There are reports however that Prime95 will throw up errors that SP2004 dosn't catch (even though they are in effect the same program.
Everest
A very thorough program that will give you various info on things such as memory bandwidth/timings and CPU settings and temperatures. This tool can also be used to find out any conflicts your PC may have with 'performance tune up'.
S&M
If you want to see your CPU to reach its max temp under current cooling conditions then this program will do it for you and also stress you PC's other main components. This program is ideal for burning in a processor as you can set it to loop certain tests and it will not stop if it fails although it will tell you it has failed. - A perfect overnight stressor!
2. Installation (Dual core)
Most of the above programs are relatively easy to setup and use, just point and click. For Dual core users though a little extra is required for SuperPI and Prime 95.
For either of these programs to be run successfully and be used as a 'true' representation of stability in a dual core environment TWO versions need to be running simultaneously as you have in effect TWO CPU's (or rather two cores) . To do this and to prevent unexpected errors you will need to run the two .exe's from separate directories.
Super PI
1. Extract the downloaded SuperPI mod.exe to the desktop (right click - extract - desktop).
2. Create two 'new folders'
3. Rename Folders (for simplicity SPI 1 + SPI 2)
4. Create a copy of the SuperPI mod.exe and paste it into SPI 1 folder
5. Cut and Paste the remaining SuperPI mod.exe into SPI 2 folder
You now have 2 separate .exe's of SuperPI which will not clutter your desktop should you get errors.
Prime 95
1. Install the program
2. Create 2 folders on the desktop and rename to Core 0 and core 1
3. Find the Prime95.exe (default: C:\Program Files\Prime95).
4. Copy 1 version of Prime95.exe into Core 0 folder and copy another version into Core 1 folder.
You now have 2 separate .exe's of Prime95 which will not clutter your desktop should you get errors.
3. Setup Prime 95
1. Start Prime95 (for dual core start from core 0 folder)
2.When the initial screen pops up (join GIMPS / Just stress testing) click on 'just stress testing.
3. (dual core) Click on advanced then affinity
4. (dual core) Uncheck the 'let program run on any CPU' box
5. (dual core) Set the 'Specific CPU to run on 0
6. (dual core) Start other version of Prime 95 (core 1 folder) and apply steps 3-5 but this time set it to run on CPU 1
7. Click OK
8. Now go to Options and click torture test
Now we need to decide which test to run. AFAIK the tests run like this:
small fft - CPU
large fft - CPU+Memory controller
Blend - A blend of above but with lots of physical memory used
For now we will stick with small fft so...
9. Check small fft and click ok (dual core users obviously need to do this for each instance of Prime95)
This will start a looping test (on each core). This test will run indefinately or until you stop it or it produces and error.
Dual core uses should see 100% usage on each core(which shows as 50%+50%=100%) while this test is running (press CTRL+ALT+DEL > Performance tab). It makes no difference to set affinity of prime 95 in the traditional way process(rightclik process>set affintiy) as the application is controlled by prime and not windows although it dosn't hurt to do that if you so wish.
4. Testing stability
This is a highly debated topic and one I do not claim to be an 'expert' on. I will give you my opinion on the quickest way to test for stability but please don't flame me.
1. The quickest half decent test is to run 1m of super PI as this will only take 30 secounds and will throw up an error if your stability is way off. If it dosn't pass 1m superPI you will need to check your overclocked settings and/or memory timings as this is by far the easiest test to pass.
2. If you pass SuperPI 1mb then go on to do a 32m pass which will take around 30 minutes to complete and will stress your CPU and memory for longer. A 32m pass is a fair indication of stability although not a TRUE indication of a stable system imo. For that you will need Prime 95.
3. If SuperPI has passed without problems then you can go onto Prime95. This is where it becomes tricky so I suggest sticking to the 'overclocking guide' and testing each individual component seperately to give an indication of where the problem in stability lies. For 'extreme' stability that is required for folding etc then a minimum 24hr pass on all three tests (small,large and blend) 'should' be sufficient although I have had a cpu that failed prime after 32 hours! I would call that stable enough tbh. For the average joe who uses his PC for a majority of tasks(gaming,encoding etc) I would suggest a 12hr pass minimum.
Many people report that they have failed prime instantly and yet continue to use there PC's without a hitch. Well all I can say is good luck to them. Personally I like to know that my PC is stable and if an error is thrown out by Prime then your PC is not stable PERIOD. It has made a calculation error and errors like that lead to instability, BSOD and worst of all hard drive corruption resulting in loss of data and probable scrambled OS installation which means a reinstall. I would rather clock 100mhz less and have stability than risk a lengthy reinstall and all the associated hassle that goes with it.
Hope this is helpful to a few people and prevents the NUMEROUS stability questions regarding P95/SuperPI.
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