[主機板] RYZEN 超頻電壓問題

KK83512

剛入手左R7 1700x + Asus B350-F+240水冷
可能唔係太熟AMD底板關係，要用到1.38v先勉強超到3.9Ghz (用Offset mode)
我用HWInfo睇返的電壓數字會發現,只要我一用Prime95等STRESS TEST軟件去到Full Load時,
個底板個Vcore會即時上到1.41-1.42v附近,但CPU Package VDD個電壓會相反跌到去1.33-1.34v
我睇過文章話咁係正常,通常會用Load Line Calibration去平衡返,
但我已經試過調整Vcore Load Line Calibration,但似乎無野可以阻止個CPU Package VDD下跌咁多
究竟以上情況係正常,定係我底板供電有問題呢?

98a

Mobo CPU Voltage = the voltage given by mosfet
CPU VDD = current CPU voltage

CPU Voltage - CPU VDD = vdorp
LLC is to try minimize the vdorp, which will push harder on the mosfet. LLC↑, mobo Vcore↓

However, to stabilize the vdrop, LLC is not the only variant. Mosfet quality , circuit design will also affect the efficiency of LLC. For most of the B350 mobo, they are not using high-end VRM. Basically, B350-F Gaming is a RGB+ROG-based BIOS of B350-Plus. Nothing had changed on the design and component which help to improve OC ability.

I won't say your broad is defected. Also, LLC level should not be over Lv3.

VRM info:
https://www.hardwareluxx.de/comm ... -liste-1155146.html

KK83512

回覆 2# 98a

Thx for the link, which is quite informative.
From what I see, Asus X370 Gaming is using the same Mosfet as that of Crosshair VI Extreme which is supposed to the new flagship of X370's line. Isn't it a great deal for stable O/C if I dun want to spend necessary amount of money on a Crosshair.

Yet, even with X370, it seems to me that the potential extra speed that I could get from a new board will be fairly limited, as many of the o/c'er are getting 4.0-4.1 Ghz with reasonable Vcore given.
Looks like there is nothing I can do now to push further unless with a new board.

98a

回覆  98a

Thx for the link, which is quite informative.
From what I see, Asus X370 Gaming is using ...
KK83512 發表於 2017-8-30 21:02

The marjority of Ryzen can reactch 3.9~4.0 ghz with 1.4v ~ 1.45v

The OC-ability of X370 and B350 are similar. Not really suggest people to change there broad just for OC. I would rather wait for 3rd generation of ZEN. It may be have more hard room for OC.

I always avoid "Gaming" mobo as it most likely will be just a gimmick.

jason060188

剛入手左R7 1700x + Asus B350-F+240水冷
可能唔係太熟AMD底板關係，要用到1.38v先勉強超到3.9Ghz (用Offse ...
KK83512 發表於 2017-8-30 14:21

你個情況我都研究左好耐，發現CPU溫度越低，vdd個電壓就越高，待機時CPU溫度30度左右時vdd個電壓會接近CPU電壓，但一full load CPU溫度上到60度時，vdd電壓就會跌(比如我行3.85ghz, BIOS set CPU  電壓1.33v，行p95時CPU電壓會上到1.363v，溫度60度，vdd就會跌到1.288v 至 1.293v，如果CPU溫度高過65度vdd電壓就會跌到1.27v 以下，咁電腦就會重啟，所以溫度對超頻幾重要，之餘點解會咁，有Ching話因為溫度高電阻高！

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rockie520

i used B350 asus , before , and i oc to 3.9 (v1.35 and never can made it to v1.38) still have fps dropped issue with some retarded game. so i changed to c6h the electricity supply to CPu can pump up to 1.5v... with auto.... and i oc to 4.0 which has no issue with the suddenly FPS drop issue......

98a

你個情況我都研究左好耐，發現CPU溫度越低，vdd個電壓就越高，待機時CPU溫度30度左右時vdd個電壓會接近CP ...
jason060188 發表於 2017-8-31 11:38

   
温度↑ = 電阻↑

假設 VRM 輸出電壓一樣 (1.3v)，

idle: CPU 30c, mobo 42c。由於溫度較低，電阻較低。由 VRM 經過 circuit 時電阻較低，所以最終到達 CPU 時會流失較少電壓, i.e. CPU VDD=1.25v

Full load: 60C CPU &Mobo。由於温度較高，電阻增加。由 VRM 經過 circuit 時損失較多，所以最終 CPU 只係接收到 1.2v


所以 full load 時 VRM 亦會提高電壓。

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98a

回覆 6# rockie520

You mean you are using 4.0 with AUTO voltage?

I suggest you apply the same value on both board to verify whether it is luck or mobo issue

rockie520

回覆  rockie520

You mean you are using 4.0 with AUTO voltage?

I suggest you apply the same value  ...
98a 發表於 2017-8-31 12:04

mobo issue , cuz b350 cannot use high Voltage....   but c6h auto voltage is too high.... i think

now i set it to 1.358 and Oc 3.75   since i do not trust my diy watercool . i dont have balls to oc 4.0 with high temperature water ...

98a

mobo issue , cuz b350 cannot use high Voltage....   but c6h auto voltage is too high.... i think
...
rockie520 發表於 2017-8-31 12:06

Nope. B350-Plus still can supply 1.4v.

In BIOS, if the Vcore is reported as 1.2V, you can +0.16v in offset mode which in total 1.36v.