Recommended max voltages for E8xxx series...

[Molotov]

I'm currently troubleshooting whether my E8500 has received degradation or whether it's ATI's rubbish drivers as i'm crashing in various games and getting artifacts.

Reason being, i recently tried some heavy-ish overclocking on my E8500 and used 1.48vcore and 1.3v VTT/FSB. I know that 1.4v VTT has sort of been proven to kill the E8xxx's but i'm unsure on the vcore. I've seen on a few forums that 1.4v is as far as you should go, but then i've seen that 1.55v is the max. I'm pretty confused and require your insight :worship:

 

[Fake]

I'm currently troubleshooting whether my E8500 has received degradation or whether it's ATI's rubbish drivers as i'm crashing in various games and getting artifacts.

Reason being, i recently tried some heavy-ish overclocking on my E8500 and used 1.48vcore and 1.3v VTT/FSB. I know that 1.4v VTT has sort of been proven to kill the E8xxx's but i'm unsure on the vcore. I've seen on a few forums that 1.4v is as far as you should go, but then i've seen that 1.55v is the max. I'm pretty confused and require your insight :worship:

I got the E8500 and from the Intel site they say 1.4V is the limit IIRC. Also it depends on your cooling, I take it your on water cooling if your using 1.48 Vcore as it's a bit overkill for air cooling. I currently have my E8500 running at 4085MHz with 1.38750 Vcore (although windows is showing something like 1.34V real and 1.32 or less under full load with Prime95 stupid Vdroop) I wanna get the CPU to go faster but I think my motherboard is a bit buggy/unstable so I won't push it to much.

I'm currently using the Thermalright Ultra Extreme 120 with Scythe fan 1200RPM (VERY silent). But yea I wouldn't push it beyond 1.4V unless you got cooling. I don't think it's the high volts that kills the CPU but the heat it produces.

 

[Molotov]

I'm using the TRUE with 2 fans in push/pull. Temps at 4.5GHz and 1.48v were in the low 60's which should have been okay seeing as i wasn't loading the cpu for more than 30s running superpi 1m twice. It might be a few variables which i'm working out now. I made a really small XP install using Nlite and my XP cd so i may have deleted something critical to windows by accident. In which case, me reinstalling now should fix the problems. I just got a BSOD while browsing the desktop with stock settings too

 

[Fake]

You will need to run a stability test to make sure that your CPU is stable. I find it hard to believe you can run it stable at 4.5GHz using air cooling unless you live in Antarctica or something.

Download and run OCCT for about an hour or 2. It will stress your CPU to 100% and really raise the temps on it. If it goes beyond 70C then that's not a good sign. I wouldn't go any higher then 65C anything higher then I would start downloading or lowering the voltages.

For an even more accurate stability test download Orthos and run the blend test for several hours (roughly 8 hours) or Prime95 (small FFTs) also for several hours.

1.4V is the absolute limit I will go to on air cooling.

 

[Molotov]

Ah. I probably forgot to mention that the overclock was for a bench run for Superpi 1m. No worry though Fake i've actually found the problem. My Asus P5Q-E actually has 1/2 dodgy ram slots that i had problems with when i first got the board. I ran memtest and got 20+ errors so i moved the ram up to the top 2 slots and no errors. Ran Prime as well and don't seem to have any degredation running at my old clocks. Thanks though

 

[Fake]

Ah. I probably forgot to mention that the overclock was for a bench run for Superpi 1m. No worry though Fake i've actually found the problem. My Asus P5Q-E actually has 1/2 dodgy ram slots that i had problems with when i first got the board. I ran memtest and got 20+ errors so i moved the ram up to the top 2 slots and no errors. Ran Prime as well and don't seem to have any degredation running at my old clocks. Thanks though

Well if your doing it for benching purposes keep in mind that memory timings are also very important in SuperPI. For example at 3.6GHz with memory at 5-5-5-18 I would score something like 13s in SuperPI. At same speed with 4-4-4-12 timings I would get low 12s or mid 11s. At just under 4.1GHz (4085MHz) with timings at 5-5-5-18 I get mid 11s.

Run SuperPI at 4.5GHz with 4-4-4-15 timings with RAM running at say 950MHz (I'm guessing your running RAM with 1:1 ratio?) your looking at 9s or less

What are you getting, now you have me curious

 

[Molotov]

Well if your doing it for benching purposes keep in mind that memory timings are also very important in SuperPI. For example at 3.6GHz with memory at 5-5-5-18 I would score something like 13s in SuperPI. At same speed with 4-4-4-12 timings I would get low 12s or mid 11s. At just under 4.1GHz (4085MHz) with timings at 5-5-5-18 I get mid 11s.

Run SuperPI at 4.5GHz with 4-4-4-15 timings with RAM running at say 950MHz (I'm guessing your running RAM with 1:1 ratio?) your looking at 9s or less

What are you getting, now you have me curious

At the moment i'm getting 10.34s with 1.45GHz and OCZ pc2-8500 running at 946MHz 6-6-6-18. Stock for the memory is 5-5-5-15 but i mixed dividers to see if stability was any better and forgot to change back. I'll try again on the weekend because now i know that my E8500 hasn't degraded using those high volts and that my memory is fine, i can try and push some more using tighter timings. I've heard that lowering Trc has a direct effect on performance but i'm not really too sure.

 

[Fake]

I've heard that lowering Trc has a direct effect on performance but i'm not really too sure.

Yep, tRCD and CAS have the biggest impact on performance with RAM. Tighter the timings on them the better the performance. Problem is is that they are also more effected by instability so be careful.

Those timings you have there are VERY lose, 6-6-6-18. I don't think it's required that you run them that low unless your running your RAM at like 1200MHz or more and even then you could tighten them.

My RAM can do over 1100MHz on 5-5-5-15 timings

 

[Molotov]

Yep, tRCD and CAS have the biggest impact on performance with RAM. Tighter the timings on them the better the performance. Problem is is that they are also more effected by instability so be careful.

Those timings you have there are VERY lose, 6-6-6-18. I don't think it's required that you run them that low unless your running your RAM at like 1200MHz or more and even then you could tighten them.

My RAM can do over 1100MHz on 5-5-5-15 timings

Well seeing as my RAM will be running about 100MHz slower at 1:1 ratio i may try 4-5-5-15 and see what happens.

 

[°TheMadDutchDude°]

Doesn't seem that this post has been answered with the correct voltages.

As for the VCore, it is 1.38v safely so I would turn it down right now if I was you.

They have a max recommended voltage for a reason, this is because it is the best volts to run through it before you start causing damage. It is not because of all the extra heat it produces because as we know it can be cooled very easily. I think that this is a problem of either overclocking the graphics (a common fact of Artifacts!) or the CPU volts are stressing the CPU toooo much, I strongly recommend that you turn it down.

 

[w3bbo]

I personally don't go past 1.45v for any 45nm chips.

 

[°TheMadDutchDude°]

Fair enough. Though it is recommended you stay below 1.38 to preserve the chip's life span.

 

[Fake]

Fair enough. Though it is recommended you stay below 1.38 to preserve the chip's life span.

Voltage has little effect on the CPU so long as you keep it cool. It's heat that does the most damage. Why do you think they use LN2 for extreme overclocking?

 

[Ham]

Voltage has little effect on the CPU so long as you keep it cool. It's heat that does the most damage. Why do you think they use LN2 for extreme overclocking?

Not the case with the new chips unfortunately. They run so cool so start with that you can get into harmful voltage levels before they get too hot.

My E7200 took about 1.7v to start getting too hot. Anything under it was running about 60-65 loaded, and that's on air.

 

[Bruce Banner]

If on water you should be able to take it to 1.45