PC Restarting and DPC latency issues

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Hello All,

Since I did my upgrade to my 3770k, I have been blighted by high dpc latency on startup, making sound choppy and pretty much unusable. At boot, the DPC latency looks like the below:

dpclatency.jpg


This happens at almost every boot, literally 99% of the time. To get rid of the DPC latency and bring it down to normal levels (around 60 or so) I have to run Prime 95 at startup until the DPC levels subside (anywhere from 10 seconds of prime to 15 minutes) before I can play any games etc, because of the constant stuttering of sound.

Things I have tried include:
- Turning off multiple devices in Device Manager (including WLAN devices)
- Unplugging GPU from PCI slot and DVD Drives
- Removing and testing each stick of ram independently
- Unplugging SSD completely and running windows from HDD
- Multiple re-installs of windows
- Multiple re-installs of sound, USB, WLAN and GPU drivers
- Downclocking CPU to stock speed
- Updating BIOS
- Turning off HPET in BIOS

Having tried all of the above, still the DPC latency persists, which normally is not too much of a problem.

Recently however, My PC crashes and restarts sporadically, usually whilst in game but also on the desktop when no intensive programs are running. I have since tried a few things like upping DRAM and CPU voltages to no avail.

I am sure these issues are linked somehow and is beginning to point to my PSU (OCZ ZX 1250W). I know overheating is not the issue. At 4.6Ghz my CPU rarely goes above 60 whilst gaming and only hits 70 after a few hours of prime. My gtx 590 never goes above 50 and both have a 360 radiator to themselves with separate reservoirs.

Seriously at my wits end and desperately need any ideas or suggestions. Sorry for the long post but needed to get it out there.

Cheers.
 
are you using easytune? or any other monitoring programs? cpu-z and easytune will cause huge leaps in dpc

things to do to improve stability at stock or oc

set the bclk to 100
spam(press repeatedly) alt and f10 at splash screen to flash the back upp with the main bios version so both bios chips run the same bios
setup your memory speed/voltages or enable x.m.p
 
easytune is not installed, made sure of that when i installed all the drivers etc. CPU-Z is installed but only recently, latency problem has been going since the 3770k went on sale on ocuk.
 
try looking in the bios for c1e c state and disable it,see if that stops the latency,aslong as eist is enabled it should still downclock the cpu

another thing to test if you can is test with another branded psu
 
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tried that yesterday, C1E support is disabled as we speak, and C state tech is also disabled. PC has crashed already today within an hour of boot. No BSOD just lights out :(
 
ive seen a lot of issues with certain ocz psu's and gigabyte boards way back from x58 days,im not saying its that but id certainly test with another just to rule it out,it could be the cause of crashing and the latency?

things to try with constant random crashing is test with dram around 1.55v-1.65v esp with 16gb and test with between 1.05v-1.08v qpi/vtt
 
ive seen a lot of issues with certain ocz psu's and gigabyte boards way back from x58 days,im not saying its that but id certainly test with another just to rule it out,it could be the cause of crashing and the latency?

things to try with constant random crashing is test with dram around 1.55v-1.65v esp with 16gb and test with between 1.05v-1.08v qpi/vtt

Tried the RAM yesterday at 1.70v, a tad high I know but had to rule it out. Will try qpi/vtt now. If its my PSU its the perfect time to go, when it cant be delivered over Christmas :(
 
its not failing but they tend to have incompatibility issues on gigabyte idk why,again im only guessing but i wouldnt rule it out completely

id say 1.6v with 16gb of ram and maybe 1.06-1.08v qpi/vtt
 
Just greyed out. set dram voltage to auto, turned xmp on / off and its still greyed out. XMP profile doesn't alter the vtt either.
 
strange,its labeled as cpu/vtt on z77/68 i can adjust mine on the up4 th,yours should be adjustable also in m.i.t/advanced voltage settings/cpu core voltage control
 
ill have a look now, appreciate the help mate.

Edit - Found the right setting this time and changed it from 1.05 to 1.075 which im testing now, will report back if it works, cheers :)
 
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