The most probable reason is an illegal sumout in the Prime95 configuration.
The most probable reason is an illegal sumout in the Prime95 configuration.
When my friends FX chip runs at +400Mhz speed, everything works well—24 hour prime95 stable—but pushing it to +500mhz causes immediate issues. Prime95 freezes on two cores and reports an ILLEGAL SUMOUT, while the other two cores function briefly for a few minutes. The problem persists beyond five minutes due to initial warnings. No physical changes have been made, but the multiplier is affected and voltage slightly increases. Turbo boost remains disabled, though some power-saving features stay active because the system is idle occasionally. Temperatures stay below 65°C under load. What might be causing this?
Ryan_78 :
ive set voltage to 1.416 and it seems to work, but I cant leave it on for more than 15min without the CPU going to 75 C, I'm just going to wait for the cooler and see if the voltage helps.
Yeah till you have the new cooler you really can't do too much. Once you get the new cooler installed let us know how much your overclocking and or temps improve. Best of luck to you..
For an AMD cpu 65C is kinda high, under 60C would help. FX cpus are very temp sensitive so that could be causing the issue partly, also there is a wall around 4.8-5Ghz that most chips can not break without extremely cold temps.
By the way, it's capping at 4.3. I'll attempt the test joex444 mentioned, though it shouldn't be limited to 4.3—4.6 seems more appropriate. He'll also receive a new cryorig h7 next week, which might help. Also, the maximum temperature is 65, but I'm keeping it under 60 during testing. Only the most extreme tests push it to 65.
Ryan_78:
Just to note, it's capping at 4.3. I'll attempt the test joex444 mentioned, but otherwise it shouldn't be limited to 4.3, right? I think 4.6 would be more realistic. He's also getting a new cryorig h7 next week, I'll check if that assists. Also, the max temp is 65, but keeping it under 60 is better—only extreme tests push it to 65.
Other factors that significantly impact performance are the motherboard you're using. The VRM configuration greatly affects clock speeds. What motherboard are you running? How are the VRM temperatures? I'm hoping the new cooler will help.
It seems the board still has some restrictions even with good CPU temperatures and VRM settings. Others have tried various approaches: using an LLC configuration at very high or ultra levels, disabling Turbo core, APM, c6, and c1e, increasing the Vcore to 1.45v, raising the multiplier to 23, setting the BCLK to auto. I found this information in a relevant thread.
Ryan_78 :
ive set voltage to 1.416 and it seems to work, but I cant leave it on for more than 15min without the CPU going to 75 C, I'm just going to wait for the cooler and see if the voltage helps.
Yeah till you have the new cooler you really can't do too much. Once you get the new cooler installed let us know how much your overclocking and or temps improve. Best of luck to you..