FX 8350: OC Debugging

[TheFriendlyHacker]

I have a system with an FX-8350, and recently got ahold of a 240MM liquid cooler (Corsair H100i Pro if it matters). 

 

TL;DR - I want to overclock my CPU more. Despite temps being very low, I have absolutely no stability at 4.8ghz. But 4.7 is (mostly) fine. Is there any way to tell what specific setting in my BIOS is causing the instability? I don't think it's thermals (even at 4.7, it never breaks 45C under load). 

 

Longer version:

Ideally, I want to get my CPU up to 4.9-5.0ghz. With the liquid cooler, it's perfectly stable at 4.6 and mostly stable at 4.7. 4.8+ = insta-RIP. Temps are not a problem - even under load at 4.7, it never exceeds 45C. 

I have a Sabertooth 990FX mobo + 750W PSU, and have tried voltages ranging from 1.4 to 1.53 - no luck at all. 

 

The BSOD's I get don't really tell me what aspect of my OC is causing it to crash. Do any of y'all know a way to get some more specific info about what settings may be causing the instability? Are there any 3rd party programs that might do so? Any help would be greatly appreciated

[Firewrath9]

could be like ryzen, might hit a wall at 4.7ghz sort of like how ryzen hits a wall at 4.2-4.3.

http://hartacus.blogspot.com/2013/01/my-bios-for-fx-8350-50ghz-template.html

thats what i found for 8350 @ 5ghz.

What are your VRM tempertures?

[airdeano]

https://rog.asus.com/articles/hands-on/guide-overclocking-fx-8350-to-4-8ghz-on-crosshair-v-formula-z/

prolly the best and easiest guide for FX. used it 5 years ago for a 4.9/1.475.

memory keep it at 1333/1600 for starts.

[TheFriendlyHacker]

4 minutes ago, airdeano said:

https://rog.asus.com/articles/hands-on/guide-overclocking-fx-8350-to-4-8ghz-on-crosshair-v-formula-z/

prolly the best and easiest guide for FX. used it 5 years ago for a 4.9/1.475.

memory keep it at 1333/1600 for starts.

I actually used this exact guide to (try to) get her up to 4.8+ghz lol. From everything I've researched, my setup should be able to run at 4.8ghz at LEAST, possibly even 5. 

 

That's why I'm wondering what other variables could be affecting it, and why I wanna be able to see what specifically caused the system to crash (a BSOD saying "SYSTEM SERVICE EXCEPTION" doesn't really narrow it down haha)

[Vegetable]

My old 8350 setup with a sabertooth 990fx was a champ. I could do 5ghz 1.52v on my 280mm x61 aio at like 50-55c under powerMAX for hours. I remember 4.7ghz was 1.45v, 4.8ghz was 1.47v, and 4.9ghz was at 1.49v. All of those are with LLC turned on high so it wasn't drooping any and in fact was always about +.01v higher than what I had set in bios, but it was perfectly stable for all those listed above. *disclaimer* I had a pretty golden 8350 so if you didn't win the silicon lottery don't expect to copy paste my settings and it work/be stable. Hope I helped

[airdeano]

voltage, VRM temperatures, or ability of the silicon.

BSOD usually has a code error.

[TheFriendlyHacker]

1 minute ago, Vegetable said:

My old 8350 setup with a sabertooth 990fx was a champ. I could do 5ghz 1.52v on my 280mm x61 aio at like 50-55c under powerMAX for hours. I remember 4.7ghz was 1.45v, 4.8ghz was 1.47v, and 4.9ghz was at 1.49v. All of those are with LLC turned on high so it wasn't drooping any and in fact was always about +.01v higher than what I had set in bios, but it was perfectly stable for all those listed above. *disclaimer* I had a pretty golden 8350 so if you didn't win the silicon lottery don't expect to copy paste my settings and it work/be stable. Hope I helped

The "Silicon Lottery" is starting to become my biggest fear lol. I picked up this desktop from work because my company had decided it was inoperable (literally just the front IO doesn't work....kinda embarassing to ditch the whole system just for that, considering I work for an IT company lol). 

 

But. I don't know how old this CPU is...er rather, how it's been used/what it's been put through. So it is possible that I just drew a short straw. But I'd like to "prove" that, if that makes sense

[TheFriendlyHacker]

I also feel like mentioning that I only have 1333mhz RAM, OC'd to 1600mhz (system doesn't even try to boot if I push it farther than that). I doubt this is relevant...but...who knows

[aezakmi]

VRM could be the problem, but after years of having one I found out stability problems start after hitting a x22 or higher multi setting, the ideal is to keep it under 20, dunno how, dunno why but it works like a charm

 

remember to tune the HT frequency too, keep it under 3000MHz

you'll gain performance by rising the FSB frequency and lowering the CPU multiplier, for example, a 200*23.5 config is worse than a 250*19 config despite both having similar CPU clock speed, I was able to hit 275*18 (4950MHz) on my 8350 at 1.48V with both the Sabertooth R2 and an MSI GD65v2

 

problems with this kind of overclock are 

• memory speed, if you don't tune it and the latencies you'll get instant BSODs
• northbridge temps, starts to skyrocket to 90C after 240MHz
• HT frequency, anything over 3000MHz will make the CPU fail any floating point test

 

[TheFriendlyHacker]

6 minutes ago, aezakmi said:

VRM could be the problem, but after years of having one I found out stability problems start after hitting a x22 or higher multi setting, the ideal is to keep it under 20, dunno how, dunno why but it works like a charm

 

remember to tune the HT frequency too, keep it under 3000MHz

you'll gain performance by rising the FSB frequency and lowering the CPU multiplier, for example, a 200*23.5 config is worse than a 250*19 config despite both having similar CPU clock speed, I was able to hit 275*18 (4950MHz) on my 8350 at 1.48V with both the Sabertooth R2 and an MSI GD65v2

 

problems with this kind of overclock are 

• memory speed, if you don't tune it and the latencies you'll get instant BSODs
• northbridge temps, starts to skyrocket to 90C after 240MHz
• HT frequency, anything over 3000MHz will make the CPU fail any floating point test

 

Hmm, that's interesting - I never tried that approach. So basically, increase the BUS speeds somewhat and decrease the CPU multiplier to get the same result? My VRM peaks at 51C under load (and by "under load", I mean running Far Cry 5 at ultra settings. Which is definitely not the same as a synthetic load that makes it go balls-to-the-walls, but it's fairly realistic for what I'd actually do with the CPU)

 

Also, I have 1333mhz memory that I've OC'd to 1600, but can't do any higher (system doesn't even try to boot if I go above 1600)

[aezakmi]

1 minute ago, TheFriendlyHacker said:

Hmm, that's interesting - I never tried that approach. So basically, increase the BUS speeds somewhat and decrease the CPU multiplier to get the same result?

 

Also, I have 1333mhz memory that I've OC'd to 1600, but can't do any higher (system doesn't even try to boot if I go above 1600)

if you're trying it keep the memory as close as 1333 or 1600 as possible, only add the amount in % of your FSB overclock to the memory speed

 

like, 240 FSB = 200+20%, so 1333+20% = 1599, knowing that, force the memory frequency to be 1333 on your setup, the overclock will take it to 1599 automatically. If you know the RAM works fine up to 1600MHz don't go over it, you can still overclock the CPU as long as you downclock the memory

 

In an ideal scenario in which the FSB is set to 300 you'd need to set the memory speed to 1066 so it's also gets overclocked to 1599, get it? might be complicated at first but all you need to know is to calculate percentages to compensate the overclocking

 

ps. I know the GD65v2 is able to hit 300*16.5 as I had it, but now my sister has it and well, she uses it at stock clocks because she doesn't play games, I should warn you to avoid going over 240MHz with the stock cooling on the northbridge, the ghetto solution is to mount a small 60mm fan over the heatsink so it blows the heat away, the right solution is to get a bigger heatsink, after 280MHz the VRMs will get scorching hot so you'll also need cooling for that

[TheFriendlyHacker]

59 minutes ago, aezakmi said:

if you're trying it keep the memory as close as 1333 or 1600 as possible, only add the amount in % of your FSB overclock to the memory speed

 

like, 240 FSB = 200+20%, so 1333+20% = 1599, knowing that, force the memory frequency to be 1333 on your setup, the overclock will take it to 1599 automatically. If you know the RAM works fine up to 1600MHz don't go over it, you can still overclock the CPU as long as you downclock the memory

 

In an ideal scenario in which the FSB is set to 300 you'd need to set the memory speed to 1066 so it's also gets overclocked to 1599, get it? might be complicated at first but all you need to know is to calculate percentages to compensate the overclocking

 

ps. I know the GD65v2 is able to hit 300*16.5 as I had it, but now my sister has it and well, she uses it at stock clocks because she doesn't play games, I should warn you to avoid going over 240MHz with the stock cooling on the northbridge, the ghetto solution is to mount a small 60mm fan over the heatsink so it blows the heat away, the right solution is to get a bigger heatsink, after 280MHz the VRMs will get scorching hot so you'll also need cooling for that

Thanks for the info! I'll give it a try later today. 

 

I've got that liquid cooler for my CPU, and 3 120mm fans in the case for everything else (not to mention, the 2 120mm fans on the water cooler which blow air into the case...not sure if that's good or bad lol). 

 

I'll take a shot at increasing the BUS speeds and see what I can get away with. Unless I happened to get the runt of the litter with my 8350, it really should be able to clock higher than 4.7ghz. Especially considering the liquid cooler + the mobo I have.