• Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

Ryzen DRAM Calculator and tRFC

mgilbert

New Member
Joined
Sep 17, 2019
Messages
12 (0.38/day)
On the main page, the Ryzen DRAM calculator recommends a tRFC value of 288 for my RAM. However, my UEFI also asks for values for tRFC2 and tRFC4. Those values are not given on the main page. I found an online article that says tRFC2 should be (tRFC / 1.346), and tRFC4 should be (tRFC2 / 1.625). That yields values of 214 and 132 for tRFC2 and tRFC4.

However... On the "Additional Calculator" page or the DRAM calculator, there is a calculator for the tRFC, tRFC2, and tRFC4 values. When I plug in the values required, obtained from the main page, that calculator gives values of 390, 290, 178 for tRFC, tRFC2, and tRFC4.

Can someone explain the three tRFC functions - and which set of values I should use???
 
Last edited:
Joined
Jan 4, 2013
Messages
211 (0.09/day)
Location
Denmark
System Name R7 3800x@4525MHz/E5800@4GHz/Skylake 6400
Processor R7 3800x/E5800/i5 6400
Motherboard Gigabyte Master X570/Asus P5QL-EM/Asus Z170 Pro Gaming
Cooling Noctua NH15D-SE/Zalman 9500 series/Stock
Memory 16GB CMK16GX4M2B3600C18 CL14/Kingston HyperX PC8500 - 4GB/G.Skill Ripjaws 32 GB F4-3200C16D-32GV
Video Card(s) R7/HD7800XT / R290X
Storage Aorus 2TB Corsair MP600 + 960 Evo 1TB/Seagate 7200 series 12, 11, 10 and 9 / 2xSamsung EVO 850 500GB
Display(s) 2x Acer P243w and 1 Acer G245h in the midle
Case Custom builds
Audio Device(s) -
Power Supply Silverstone 850watt modular Gold/Gold Silverstone 850watt/1000Watt Antec
Software win10pro / Win10 Home / win7 / wista 64 bit and XPpro
Just leave them to auto, if the the rest fint and you cant thighten cl more then try to lower trfc and then the rest. I found that trfc could go down by 5 points at the end of tweaking
 
Last edited:
Joined
Sep 3, 2019
Messages
119 (2.59/day)
Location
Thessaloniki, Greece
Processor Ryzen 5 3600
Motherboard Gigabyte X570 Aorus Pro
Cooling Corsair H110i 280mm
Memory Corsair Vengeance LPX DDR4 3466MHz CL16-18-18-36 1T, B-die @3800 CL16-17-16-32 1T (1:1:1)
Video Card(s) ASUS RX580 DUAL 8GB
Storage Samsung NVMe 970Pro 512GB / SATA-III 850Pro 1TB SSD
Display(s) 24" EIZO FlexScan S2411W 1920x1200
Case None
Audio Device(s) Sound Blaster Z / Logitech Z5500 5.1 500W
Power Supply Corsair HX750i
Mouse Logitech MX Master
Keyboard Logitech G15 v2
Software Windows 10 Home 64bit
On the first (main) page of DRAMcalc, after you click the "R - XMP" button what is the tRFC ns you see on first column? What profile version are you using (V1, V2) and what frequency (MT/s)?
 

mgilbert

New Member
Joined
Sep 17, 2019
Messages
12 (0.38/day)
On the first (main) page of DRAMcalc, after you click the "R - XMP" button what is the tRFC ns you see on first column? What profile version are you using (V1, V2) and what frequency (MT/s)?
260 nS, V1, 3,000 MT/s...
 
Joined
Nov 11, 2004
Messages
4,279 (0.78/day)
Location
Formosa
System Name Overlord Mk MXVI
Processor AMD Ryzen 7 3800X
Motherboard X570 Aorus Master
Cooling Corsair H115i Pro
Memory 32GB Viper Steel 3600 DDR4 @ 3800MHz 16-19-16-19-36
Video Card(s) Gigabyte RTX 2080 Gaming OC 8G
Storage 1TB WD Black NVMe (2018), 2TB Viper VPN100, 1TB WD Blue 3D NAND
Display(s) Asus PG27AQ
Case Corsair Carbide 275Q
Power Supply Corsair RM750
Mouse Logitech G500s
Keyboard Wooting Two
Software Windows 10 Pro
Benchmark Scores https://valid.x86.fr/ztiub6
Are you sure you're using the latest version?
They're in the DRAM calculator, but it also says to there's no need to change them on Ryzen processors.
 

mgilbert

New Member
Joined
Sep 17, 2019
Messages
12 (0.38/day)
Are you sure you're using the latest version?
They're in the DRAM calculator, but it also says to there's no need to change them on Ryzen processors.
Yes - version 1.6.2, downloaded yesterday, from this website. The tRFC value is listed on the main page, but not the tRFC2 or tRFC4 values. There is a calculator for determining tRFC and those two extra values on the "Additional Calculators" page, but it returns a different tRFC value than the one on the main page. My BIOS asks for all three, and there is no "Auto" for any of the three. I'm sure I can get away with using the more conservative values provided by the calculator on the "Additional Calculators" page. I can't imagine it would make much difference.
 
Joined
Sep 3, 2019
Messages
119 (2.59/day)
Location
Thessaloniki, Greece
Processor Ryzen 5 3600
Motherboard Gigabyte X570 Aorus Pro
Cooling Corsair H110i 280mm
Memory Corsair Vengeance LPX DDR4 3466MHz CL16-18-18-36 1T, B-die @3800 CL16-17-16-32 1T (1:1:1)
Video Card(s) ASUS RX580 DUAL 8GB
Storage Samsung NVMe 970Pro 512GB / SATA-III 850Pro 1TB SSD
Display(s) 24" EIZO FlexScan S2411W 1920x1200
Case None
Audio Device(s) Sound Blaster Z / Logitech Z5500 5.1 500W
Power Supply Corsair HX750i
Mouse Logitech MX Master
Keyboard Logitech G15 v2
Software Windows 10 Home 64bit
Try both... first use the one on main page and calculate the tRFC2/4 by the... (tRFC / 1.346), and tRFC4 should be (tRFC2 / 1.625) rule.
You can try the alternative also from the main page. And you can try later the values on the "Additional Calculators" page.

Mine too gives different tRFCs between the pages (ver1.6.2).
Maybe the one on Additional Calculators is more of a standar/typical for the given MTs/s and tRFC ns, and the one from main page is in correlation with the other settings (safe/fast settings)
 
Joined
Mar 22, 2019
Messages
174 (0.82/day)
Location
Western NY, USA
Processor AMD Ryzen 7 3700x (Upgraded from R5 2600 @ 4 GHz)
Motherboard Asus ROG Strix B450-F Gaming (BIOS 2801 - AGESA 1.0.0.3ABBA)
Cooling Arctic 33 Esports Edition Dual Fan
Memory G.Skill Trident Z RGB 3200 Mhz (F4-3200C16D-16GTZR) @16-17-17-16-34-54
Video Card(s) MSI GTX 1660 TI Armor 6G OC @ 2085 MHz
Storage 3x Crucial MX500 / 1x Samsung 850 EVO / 4 HDDs
Display(s) Dell 23" LCD S2316M
Case Rosewill Challenger (w/ Modified Side Panel)
Power Supply Rosewill Photon 750
Mouse Cooler Master MS120
Keyboard Cooler Master MS120
Software Windows 10 Home x64
What CPU and Motherboard/BIOS do you have ?
If you have a 3000 series CPU, you might need to wait for a BIOS update that improves Memory OC performance/Compatibility.

I used the DRAM Calculator when I had a Ryzen 5 2600 (OC'd to 4GHz) on an Asus ROG Strix B450-F and it worked great.
BUT, I tried it for my current 3700x (with the same RAM) and I can't OC any better than the DOCP (XMP) profile besides lowering some of the Primary timings.
I'm 99.9% sure it is a BIOS issue. so hopefully at some point I will be able to get my RAM back to 3400 MHz with tighter timings like I did with my 2600.
 

mgilbert

New Member
Joined
Sep 17, 2019
Messages
12 (0.38/day)
Try both... first use the one on main page and calculate the tRFC2/4 by the... (tRFC / 1.346), and tRFC4 should be (tRFC2 / 1.625) rule.
You can try the alternative also from the main page. And you can try later the values on the "Additional Calculators" page.

Mine too gives different tRFCs between the pages (ver1.6.2).
Maybe the one on Additional Calculators is more of a standar/typical for the given MTs/s and tRFC ns, and the one from main page is in correlation with the other settings (safe/fast settings)
That sounds like a good plan. Thanks...

What CPU and Motherboard/BIOS do you have ?
If you have a 3000 series CPU, you might need to wait for a BIOS update that improve Memory OC performance/Compatibility.

I used the DRAM Calculator when I had a Ryzen 5 2600 (OC'd to 4GHz) on an Asus ROG Strix B450-F and it worked great.
BUT, I tried it for my current 3700x (with the same RAM) and I can't OC any higher than the DOCP (XMP) profile besides lowering some of the Primary timings.
I'm 99.9% sure it is a BIOS issue. so hopefully at some point I will be able to get my RAM back to 3400 MHz with tighter timings like I did with my 2600.
Well, I'm still on an ASRock x370 board with a Ryzen 1700 processor. I'm going to upgrade, but I just can't afford it right now.
 
Top