790 corruption issues?

[saaya]

Who knows, maybe that BIOS is the miracle evga users are waiting for and it deals with the corruption too.
But now that I have seen the poll results and with that many people NOT having corruptions at all, I would REALLY like to try this board on my own and test it myself.

i dont know man, according to the poll its still 50/50 for the ref boards and 60/40 for the asus boards. if half the people DO have corruption issues thats a very large number. what concerns me is that some people do not have any coruption issues whatsoever even when overclocking. so it sounds like only some boards are affected. if thats the case then it really sucks...

i wanna try 790 too to make a map of the stable and unstable fsb/mem combinations

Hey Saaya,

Nice to see someone finally taking notice!

Seems to me the issue is pretty widespread, plenty of ppl over at the EVGA forums are complaining about freezes/hangs/lock-ups during video playback and during some other tasks aswell. I have multitudes of terabytes of HD content so the issue was apparent to me almost at once and I found that just sitting idle in the CRYSIS game menu's would cause the same hang-ups(during one of these hangs my CRYSIS installation was !!C-O-R-R-U-P-T-E-D!! but the rest of my OS was left intact!) I began investigating the issue very carefully and I found through trial and error (ie: infinite looping x264 + stop watch) that I could control and duplicate the system hangs and data CORRUPTION by manually adjusting the FSB + GTLREF Voltages alone.

I did my adjustments from the BIOS since this is my personal computer and I have it installed in a case nestled into my desk etc.. I do work in a small boutique and I'm resposible for system design and overclocking(all of our rigs are OC'd) but in the same breathe I've got this 790iU for myself and so that I can get to know it very intimately for all future commercial builds we will do based on it...

Cheerz

nice! if its gtlref and vtt then this makes sense! that would explain why for some people the board works and for others it doesnt since every cpu reacts different to gtlref and vtt

so for some cpus those volts are too high, for some cpus they are too low...

i have a feeling your instabilities might have been cpu related though and not chipset/mem related like the corruptions most people here experience.
but then again, who knows, maybe the boards are different and so everybody is actually experiencing cpu instabilities cause on the 790 boards you need other gtl and vtt voltages to reach the same cpu speeds stable...

from what i thought i knew negative values are the ones to go for when pushing high FSB but that is such a generic statement and one i can't back as i never did any actual testing to prove either way

i think thats only the case on asus boards, they have relatively bad gtl implementation and have way too high tgl once you increase vtt.
gtl is supposed to be 66% of vtt, but with higher vtt, its more like 80% or even more.

remember fsb swing? its a really low voltage, ive been thinking this could be the 0.4v "line" that is used to measure a logical 0. fsb swing is supposed to be 1/4 vtt. so we have vtt, gtl ref, and fsb swing, which from my understanding are used to interpret a 1 or 0.

high = vtt
ref = cpu gtl
low = fsb swing

1200mv
800mv
400mv

i dont know how exactly gtl works, but i assume a "wave" has to be between 800 and 1200mv to be detected as a logical 1, and between 800mv and 400mv to be detected as a 0. if we increase the clockspeeds the transistors will push the voltage up and down faster, meaning the "waves" will not be as high and the valleys between the waves will not be as low anymore. so then its hard to tell when its a 0 and when a 1. so in this case reducing vtt would make it easier to detect 0s and 1s again. i think thats why intel reduced vtt to 1.2v in their latest cpus from 1.4v originally.

i dont think we need fsb swing and vtt, what we really need to adjust is just gtl voltages. as long as a "wave" is above gtl, it will be a 1, and if its below it will be a 0, it doesnt matter how close it is to the vtt line and the vfsb swing line. ...i think!

but having vtt and gtl adjustable is nice, cause we have 2 ways to adjust gtl then. we can either widen the window which will increase gtl milivolt wise and push the window up, or we can adjust the ratio, increasing or decreasing gtl in rough steps in milivolt. but of course, the best would be if we could adjust gtl ref in very fine steps with dividers, since there are other voltages related to vtt, such as nb gtl

5010 from your results it looks to me like your board has too low gtl settings, its most likely below 66%, and when you increase vtt its probably even more off and higher, just like on the asus boards i meassured. are you using the asus S2E or a 790 ref board? asus right?