Only 2 cores shown working most of time on Intel i7-3770K

[hpxref]

System: ASUS p8Z77 Vpro mobo, 16GB ram, Liquid cooled CPU, Win8.1 PRO 64bit
Mobo Bios v1616 (original, not updated), Intel i7 3770K cpu, HD4000 graphics
BIOS shows all 4 cores set to All
Question: Been using video software thats supoposed to use all 4 cores (system was built to suit video software) but has been noticable slower than other users despite upgrading RAM to Gskill 2400
Asus mobo comes with AI utility soware, and have noticed it shows only 2 cores running under "CPU" This double checked with CPUID which also shows the same, only 2 cores.
Occasionally on reboot Ai will show 4 cores running, as then does CPUID also, but this very infrequent, maybe 5% of the time on a reboot.

CPU voltage standard at 1.056V showing on AI/CPUID and BIOS
Clock speed at standard 3.5GHz (it is normally ran at std clock speed as Video software often crashes, though exactly the same at 4220Mhz clock rates, so is a software problem, not hardware)

Ive changed my RAM setting GSkill 2400 ram back to 16GB of 1600 RAM (Kingston) jus\t in case, but this changes nothing.
BIOS default settings used

Odd note: If I change the number of cores in BIOS it makes no difference, Ie: changing cores to 1 on BIOS and on reboot, both AI and CPUID still say 2 cores running !! ???
Question: Is my CPU faulty (its still under warranty) or is this a known problem on the ASUS mobo ime using?
Asking you guys rather than contact Intel at thus stage as it seems you all know a lot more!!
John

 

[i7Baby]

It uses what it needs to handle the load. Try a burst of Prime 95 to see it cycle through all the cores.

 

[Deuce65]

CPUID should show 4 cores\8threads regardless of load. Try this,
start > run > msconfig
go to boot tab,
advanced options
make sure number of processors is unchecked (fix it if it is messed up).

 

[hpxref]

CPUID should show 4 cores\8threads regardless of load. Try this,
start > run > msconfig
go to boot tab,
advanced options
make sure number of processors is unchecked (fix it if it is messed up).

 

[hpxref]

Thanks night owl, tried that ands it seems to be holding now at 4 cores showing during reboots...msconfig showed 1 "cpu" , but I changed it to 4 !!
(I should have changde it to 0?.. are the cpus meant here to be the cores?)
If it reverts back I shall change number of cpus to 0 as you suggest

 

[Deuce65]

Yes the CPUs are cores. You can either select the correct amount or uncheck it and let Windows figure it out on its own. Either setting should have the same result.

 

[hpxref]

Thank you Duece65 I appreciate your time in answering....my decision to change the cores to 4 instead of unchecking it seems to have been be the safest way to do ii. It gets 4 cores up all the time now, so thank you.
However Ive ran into BIG troubles when I re booted on Win7PRO...msconfig showed already set to 4 cores, so I unchecked the box to let Windows sort it out as you suggested. BUT Win7 no longer boots up, Win Repair cant repair it, went through list of boot up entries when it tried to boot and found one where it gave the message " Unspecified changes to sysconfig might have caused the problem" So it appears the Win7Pro (latest updates from Micfrosoft) have not been able to sort it out! Been unable to get Win7 up even from previous restore point and needed it urgently as my video editing s/ware no longer works in Win8.1 as it did before l..cant make or modify DVD menus on it any more, but no probs under WIN7, Not yet been to bed since yesterday after finding a suitable drive needing backing up and reformatting then reload Win7Pro back on that with dist disk as needed to gert cpleted DVDs out today....5:30pm now not yet had any sleep.
msconfig was carefully changed to uncheck it for this app (ive been a user of config,sys since the days of Dos and since Win3.0 of awful memory, so I have some expertise in that area... but have left Win7/8 internal changes strictly alone till now. too big a drum of worms best left to others like yourself brave enough to tackle it)
Now I can look at the stiffed Win7 disk with DOS under Wins repair module , tried looking at the disk with that, but even thats restrictive
Any other way to access the drives msconfig either with DOS or other disk editing software that you may know of? (which works under Win7/8 with large drives) ??
Again thanks
John