Jump to content
HWBOT Community Forums

Recommended Posts

Posted

Anyone here tried TEC cooling for NB? I want to check my REX with 186W TEC cooled by cold water (+10-12C) to see if it will allow me to go higher than 650-660mhz posssible with stock heatsink. I also have issues running high fsb over 600-620mhz with non "1:1" memory dividers and hope cooling will resolve this. I know the best is to put pot on nb but I need first to setup memory properly (i.e. 666fsb strap 400 2:3) before going ln2.

Posted

Funny story about NB cooling. When I ran it previously, I used a Tek Slim sitting on the stock heatsink. I had no issues pouring the Tek full pot and the probe dropped down to about -190 or so. This is when I hit 670 FSB for the first time.

 

On my most recent run, I actually acquired a legit NB pot and used heatsinks on the VRM's, etc. I found out that the cold bug on the NB is about -45°C. Basically, putting the Tek on the NB heatsink was virtually ineffective since -190°C on it didn't even translate to -45°C at the chip.

 

Next time I take the board cold I'll see if the NB pot makes a difference for FSB since I was just pushing my E8600 last time and FSB didn't need to be above 650 or so with that for the benches I was running.

  • 2 weeks later...
Posted

Anyone knows if E8xxx are fsb limited with air? I have put my single stage on NB (-28C load) and cannot jump over 630fsb (630*6) with cpu cooled by all-in-1 water cooling at any strap/setting (before, I was able to push it to 660fsb with 1:1 cooled by ss). CPU itself is capable at least 4400-4600 at this cooling.

Also, it seems like I should use single sided memory to go high memory clocks over 600 mhz fsb.

Posted

I can confirm cold on nb helps and wolfdales are bclk-dependant on temperature. With cpu@186W tec and nb @ss I can now boot to windows with 650fsb and high memory multies - however tec is not enough to make me run any tests (anyway, it was not able to boot windows with water cooling only @650fsb). Actually, cpu requires 1.75 vtt and gtl tweaking to go that high with water/tec. Maybe that is cpu that sucks but this wolfdale really scales with cold in terms of fsb in my test.

Posted

I have issues with my REX not posting after testing SS on nb (probably mositure somewhere under socket/nb) so cannot be 100% sure. Should complete the vpll mod later today if I fix an issue. vpll transistor is on the back side of the motherboard and I was not able to track the IC that controls the gate of this transistor. I think there may be two options - to control the gate with external resistor divider (this mod will allow switching back to normal mode) or trying to tie the gate to ground with resistor (but this will depend on PWM IC if it will stand it).

Posted (edited)

Okay, here is the story on vpll mod for REX:

1. vpll is controlled with AS324 above PCI-E x1 slot. AS324's non-inverting input is controlled by DAC and we need to disconnect this DAC from pin 5 of AS324 and set the voltage on this pin manually. I had issues trying to lift the leg of AS324 and broke it so I had to completely remove AS324 and replace it with LM324 (same as AS324):

b35136ccdaf7.jpg

2. Before soldering LM324 back I have lifted up the 5th pin of this IC (the picture also indicates how to connect multiturn trimpot to lifted pin of LM324/AS324):

a15b1e5dbd57.jpg

3. 1st and 3rd pins of trimpot should be connected to 3.3v and ground respectfully, middle pin should be connected to lifted pin of LM324:

29ceef3761a2.jpg

4. The result is you can set any voltage you want in 0-3.2 range for pll, turning the trimpot:

ed678661ab12.jpg

 

Tips:

1. You can use any trimpot however I recommend using >1kOhm. It acts as resistor divider that allows setting voltage on the middle pin in the range from ground to 3.3v (or 12v if you connect your trimpot to 12v).

2. I recommend that you use 65nm cpu - in case something goes wrong (wrong point of trimpot connect or disconnected wire etc) the maximum of 3.3v will go to cpu pll which is still safe for some time for 65nm cpus. Or, to be maximum safe, use no processor at all and check the pll voltage with motherboard started on the back side of motherboard here:

b5da33bd7019.jpg

3. To be on a safe side and get 1.65-1.7v on initial startup I recommend that you set trimpot in the middle (so for 1kOhm resistance between left pin of trimpot and middle pin should be 0.5kOhm, for 10kOhm trimpot - 5kOhm etc).

Edited by TerraRaptor
  • Like 2
  • Thanks 2
  • 2 months later...
Posted

This topic is interesting, but regarding the lower PLL I can't say I had similar reesults, in fact lowering PLL gave me a worse CB. It is a balancing act really, similar to x58, lower is not always better and vice versa.

  • Like 2
Posted (edited)

Hey Guys!

I'm having trouble to go over 500fsb with this board. I mean, it's a rampage extreme, and it SHOULD be able to go between 500/550fsb with almost everything set to auto.

I tweaked all voltages settings but got nothing (i even went to the "red" zone!), 500fsb barrier is to low for this amazing board.

I'm using a qx9650 and corsair ddr3 dominator 1800mhz/7-7-7-20 and even when lowering their frequencies the system hangs during post or, with lucky, when entering windows 7.

 

Any tips/ideas? I'm using 2x120mm vardar fans at 2200rpm all the time to cool nb and chipset, and H100 to the cpu.

Edited by Casanova
Posted

@svictorcc, 500 FSB with a quad core is actually pretty high, especially for auto settings. If you're just trying to push your QX9650, you'll probably do better around 400 FSB and by using the multiplier.

  • Like 1
  • 2 years later...
Posted
On 2/25/2016 at 8:40 PM, TerraRaptor said:

High vpll moves up the fsbwall on 65nm cpus, low vpll is said to move coldbug down with 45nm cpus. Important note is 45nm cpus will die extremely fast if moving over 1.7-1.8v.

2 years ago you posted that vpll mod for the REX board. any chance to get this working on a p5e3 premium ? :)

  • Confused 1
Posted (edited)
8 hours ago, TerraRaptor said:

I have P5E3 Premium so I will try to find time to look into mod in next few weeks.

i think we can adopt this with 80% to the p5e3. but i have issues to find a voll measuring point and some other things.

Edited by Gigelz
  • 1 month later...
Posted
On 9/18/2015 at 8:15 PM, Calathea said:

 

Fun to see so many people sharing s775 goodness. Here's how I insulated the board, I had too much free time back then :D F1EE and some kind of duniek or ryba nb pot.

 

PB050098_zpsfbqrlh1j.jpg

why you not cover vrm parts? they will be the first to get wet under load in nitrogen smoke

  • Confused 2
  • 3 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...