Ryzen 3900X thread

[Jamin280672]

Also what should I setting FCLK and SOC to? I'm using 4000 memory and it's set to auto, should I downclock the memory and adjust FLCK manually? What's going to optimal?

How do I even check what FCLK is set to on auto?

What is your ram timings rated for at 4000mhz ? remeber if you are shaving 400mhz off the speed and setting it to run at 3600mhz, you can tighten up the timings to make up for the loss of mhz, so 4000mhz CL18 should easily do 3600mhz CL16, use RyZen DRAM calculator to get a better picture of what you can try and aim for: https://www.techpowerup.com/download/ryzen-dram-calculator/

As for FCLK, just set to half of your RAM speed, so 3600/2=1800, not a lot of CPU's will do much better than 1800 easily without loads of tweaking, to see what that is currently running at, open CPU-z select the memory tab, at the top it says NB Freq, thats your FCLK speed.

CPU Voltage leave on auto, dsont worry about 1.45v, thats perfectly normal, and it will also want close to that for a single core boost, with you hard setting it you are effectively restricting how far the CPU will boost in single core applications etc, it will always drop itself down to around 1.3v and lower in multicore, especially heavy loads.

 

[Panos]

I tired the 1usmus profile and my score in r20 dropped from 7248 to 7115.

I did run about 5c cooler on the run though around 62c max.

Changed the settings back - enabled PBO in BIOS and using Ryzen balanced power plan brings the score back up to 7282.

1usmus profile is for light loads like gaming not all core benchmarks

 

[ebilcake]

What is your ram timings rated for at 4000mhz ? remeber if you are shaving 400mhz off the speed and setting it to run at 3600mhz, you can tighten up the timings to make up for the loss of mhz, so 4000mhz CL18 should easily do 3600mhz CL16, use RyZen DRAM calculator to get a better picture of what you can try and aim for: https://www.techpowerup.com/download/ryzen-dram-calculator/

As for FCLK, just set to half of your RAM speed, so 3600/2=1800, not a lot of CPU's will do much better than 1800 easily without loads of tweaking, to see what that is currently running at, open CPU-z select the memory tab, at the top it says NB Freq, thats your FCLK speed.

CPU Voltage leave on auto, dsont worry about 1.45v, thats perfectly normal, and it will also want close to that for a single core boost, with you hard setting it you are effectively restricting how far the CPU will boost in single core applications etc, it will always drop itself down to around 1.3v and lower in multicore, especially heavy loads.

That's interesting, not sure I'm comfortable with that, i'll play around with it but if I can't see any benefit I'll leave at 1.380C. How often does the single core boost kick in?

Yes, I'll play around with the memory timings effectually, currently running at 1833/3666 which so far has been fine. Went up as high as 1900/3800 and it crashed shortly after getting into windows, which wasn't much of a surprise really.

EDIT: Not sure how accurate DRAM Calculator is, seems to suggest cl16 should be fine, FAST suggests cl14 actually, not sure about that.

EDIT:2 Yeah, thought it was too good to be true, encouraged by DRAM Calculators recommendation I changed to manual and tried cl16, wouldn't boot and had to clear cmos.

 

[Jamin280672]

That's interesting, not sure I'm comfortable with that, i'll play around with it but if I can't see any benefit I'll leave at 1.380C. How often does the single core boost kick in?

Yes, I'll play around with the memory timings effectually, currently running at 1833/3666 which so far has been fine. Went up as high as 1900/3800 and it crashed shortly after getting into windows, which wasn't much of a surprise really.

EDIT: Not sure how accurate DRAM Calculator is, seems to suggest cl16 should be fine, FAST suggests cl14 actually, not sure about that.

EDIT:2 Yeah, thought it was too good to be true, encouraged by DRAM Calculators recommendation I changed to manual and tried cl16, wouldn't boot and had to clear cmos.

Single core boost kicks in all the time, anything running that isn't heavy loading the cpu, you can easily monitor it with cpu-z, the voltages were a big worry for everyone in the beginning of Ryzen 3000, it was all over the tech news, AMD reassured everyone that it was normal behaviour for these chips, it's not voltage that kills the chips, it's current.

So 1.45v is perfectly fine for light load, 1.325v is max for heavy load, the CPU will make sure it adjusts itself accordingly as it draws more current and generates more heat, the core speed will drop along with the voltage.

As for ram, my 3900x won't do 1900mhz fclk either, I'm maxed out at 1866 fclk @ 1.075v soc, CPU on stock and the ram running at almost stock timings, 3733mhz 18 22 22 38 gear down mode enabled 1.35v, my ram is hynix CJR based, stock is 18 22 22 42 1T 3600mhz.

I can get it to do 16 19 19 39 gear down enabled 3600mhz but need 1.45v and soc voltage of 1.15v to keep it stable there, compared to what I'm running it at now, it's not worth the extra heat and voltage.

There is a way you can possibly run your ram at 4000mhz providing the mem controller can handle it, there is a setting in the bios......I'm running an MSI board, so on my board it's called uclk, set that to x2 and then hard set your fclk to 1000mhz, along with your ram to 4000mhz, this runs the fabric in a 2:1 mode, it does have some performance impact, but if it performs better than running 3600mhz 1800mhz fclk then it's still a win.

 

[Skynet5]

Single core boost kicks in all the time, anything running that isn't heavy loading the cpu, you can easily monitor it with cpu-z, the voltages were a big worry for everyone in the beginning of Ryzen 3000, it was all over the tech news, AMD reassured everyone that it was normal behaviour for these chips, it's not voltage that kills the chips, it's current.

So 1.45v is perfectly fine for light load, 1.325v is max for heavy load, the CPU will make sure it adjusts itself accordingly as it draws more current and generates more heat, the core speed will drop along with the voltage.

As for ram, my 3900x won't do 1900mhz fclk either, I'm maxed out at 1866 fclk @ 1.075v soc, CPU on stock and the ram running at almost stock timings, 3733mhz 18 22 22 38 gear down mode enabled 1.35v, my ram is hynix CJR based, stock is 18 22 22 42 1T 3600mhz.

I can get it to do 16 19 19 39 gear down enabled 3600mhz but need 1.45v and soc voltage of 1.15v to keep it stable there, compared to what I'm running it at now, it's not worth the extra heat and voltage.

There is a way you can possibly run your ram at 4000mhz providing the mem controller can handle it, there is a setting in the bios......I'm running an MSI board, so on my board it's called uclk, set that to x2 and then hard set your fclk to 1000mhz, along with your ram to 4000mhz, this runs the fabric in a 2:1 mode, it does have some performance impact, but if it performs better than running 3600mhz 1800mhz fclk then it's still a win.

Out of interest how do people test their FCLK?

Mine seems to boot happily at 1900 and I can do some cinebench runs. Not done my 300% hci test yet though.

 

[Jamin280672]

Out of interest how do people test their FCLK?

Mine seems to boot happily at 1900 and I can do some cinebench runs. Not done my 300% hci test yet though.

Most of the time you know its stable, otherwise you'd get random reboots in windows every 15 to 30 mins, not BSODs, just straight off and restart, but to be sure, id run memtest overnight which is what im just about to fire up for the night now after passing 8 hours of realbench.

The new memtest is very well worth buying, makes life a lot easier and its on $5......works out about £4.50

 

[Subzero85]

Should I get a few good years with this cpu and a tomahawk max mobo? Pretty much for gaming

 

[Skynet5]

Should I get a few good years with this cpu and a tomahawk max mobo? Pretty much for gaming

Yes. Without doubt. Perhaps upwards of 6 before you start to feel sad.

 

[Skynet5]

Most of the time you know its stable, otherwise you'd get random reboots in windows every 15 to 30 mins, not BSODs, just straight off and restart, but to be sure, id run memtest overnight which is what im just about to fire up for the night now after passing 8 hours of realbench.

The new memtest is very well worth buying, makes life a lot easier and its on $5......works out about £4.50

You talking memtest pro? Don't you basically get pro functionality included as part of the dram calculator?

 

[LtMatt]

Out of interest how do people test their FCLK?

Mine seems to boot happily at 1900 and I can do some cinebench runs. Not done my 300% hci test yet though.

Just use the system as you normally would, play some games etc. If you get no crashes or sound crackling coming through your speakers, you are probably stable with 1900FCLK.

My chip seems to do it easily at stock voltages for CPU and SOC (1.080v). Does not seem to be much performance difference though vs 1800FCLK, small margins.

 

[Grim5]

Should I get a few good years with this cpu and a tomahawk max mobo? Pretty much for gaming

minimum 3 or 4 years I'd say.
Best case is it lasts the entire console generation- so roughly 7 years

 

[Skynet5]

Just use the system as you normally would, play some games etc. If you get no crashes or sound crackling coming through your speakers, you are probably stable with 1900FCLK.

My chip seems to do it easily at stock voltages for CPU and SOC (1.080v). Does not seem to be much performance difference though vs 1800FCLK, small margins.

That's pretty much what I did and that is my experience too.

I've put it back to 1800.

I tried to run the fast primary settings from dram calculator, failed hci memtest fairly quickly. I've gone back to safe for primaries, but tightened up some of the secondaries. Tfaw and trfc seemed to help drop the dram calc test from 180seconds to 129seconds.

 

[LtMatt]

That's pretty much what I did and that is my experience too.

I've put it back to 1800.

I tried to run the fast primary settings from dram calculator, failed hci memtest fairly quickly. I've gone back to safe for primaries, but tightened up some of the secondaries. Tfaw and trfc seemed to help drop the dram calc test from 180seconds to 129seconds.

Which test did you run?

 

[Skynet5]

Which test did you run?

Hci test. With in. Dram calculator.

 

[LtMatt]

Hci test. With in. Dram calculator.

What exact settings though, easy, latency etc?

 

[LtMatt]

What exact settings though, easy, latency etc?

Using the latency test...

 

[Skynet5]

Using the latency test...

Will check when I'm hope. Yours looks better than mine with similar settings. Except I'm at 3600 cl16

 

[Skynet5]

@LtMatt I do know my tcke is 9. I need to experiment with this one.

 

[LtMatt]

@LtMatt I do know my tcke is 9. I need to experiment with this one.

I think that option is related to the power down option, which i have disabled. If yours is set to enabled i think that value will be higher. Having power down disabled provided a small improvement to latency i believe at the expense of slightly higher power draw from the memory.

 

[Skynet5]

@LtMatt



I seem to have better timings all round. But worse performance. Guess it is the ram speed making the difference.