New PSU and MOBO and crashing like crazy

ohados

Distinguished
Mar 8, 2012
19
2
18,515
Hello mates!

i've a really serious problem and iam clueless as to the problem

i bought new parts(06/17/12) and build a new pc and i recycled some parts from the old pc

as i wrote in my specs
1.new asus mobo
2.new intel cpu 3570k
3.new psu corsair 750tx
4.new chassis lancooler pc-k63
5.16GB RAM g.skill

i used from my old pc
1.my gpu ati 4770 hd
2.2 hard drives [1.ssd 60gb 2.2TB WD caviar green]

here is the problem
about 2 weeks ago the pc started to suddenly restart
it happened without a warning while the pc was in idle mode
it just went POOF and started to restart himself several times but after 2 seconds restarted again and again and again in a non-stopping cycle


i shut down the pc waited a few minutes and plugged the psu cable again
this time the pc started loading fine but at the BIOS menu an alert showed saying
asus anti-surge was triggered.. i thought that maybe the cpu had over-heated or something of the sort
so i entered BIOS mode but saw that the temp were low
27C and the mobo was on energy saver mode
before i could do anything else the pc crashed again and started the endless restart cycle
after re-shutting it and pulling the cable out i tried to disconnect everything
i removed the WD HD, the gpu, the RAM, and re-plugged them all one by one
first the ram then the gpu
then i started the pc and everything worked out perfectly

only that again iam having the RESTART CYCLE issue
and i have no idea what to do!!!!
plus the external usb samsung drive is not working all that well... after a while it starts to beep and the icon [G:\] disappear
i re-installed the whole drivers using the asus cd but that didnt help

after updating the firmware of the external HD and the bios and installing AIDA64 extreme edition and running all sort of test including prime 95 and furmark
i can safely assume this

while the pc is connected with 2 to 5 usb and voltage after some stress (caused by games or prime 95) start to drop
at first it will transmit 5 to 5.400 v on a normal base
but after the stress it will drop to 4.600V
and will crash

one time after it reached this low i've plugged another usb and the pc just crashed and wouldnt start till i plugged out all the usb i had(save for the microsoft keyboard and mouse wireless usb)


i also took the psu to a lab and they tested it for 2 min and said that its working great
of couse they didnt plug it to a mobo and a usb TO that mobo
or tried to stress the psu

but iam clueless as to the main problem
could this be a PSU problem or perhaps a MOBO problem???

plus i've noticed that unless i unplug the PSU and wait a few seconds/minutes the 4.680v will remain and not return to a normal 5v
 

ohados

Distinguished
Mar 8, 2012
19
2
18,515