Possible to vmod a epox 4PCA3+ Rev. 2.2 ?

[corleonee]

I'm typing this on a p4 prescott 3.0 @ 3.7 on zalman aircooling on 1.6vcore (says 1.5 in PC Health Bios) My cpu got alot of potential but the vcore is holding me back
Is it possible to vmod a Epox 4PCA3+ rev 2.2 ? and how?
There is a limiter on the Epox rev 2.2 mobo which doesnt go higher then 1.6vcore the bios can go up to 1.85 bios is not the problem.
Please help me sort this out mates. I'm a soldering noob but ill take any risks.

[corleonee]

Anyone ?

[Gizmo]

Let me do some research and we'll see. It's always possible to mod a mobo. The question is, are you willing to do what it takes?

We'll need some pics of the VCore regulator on the mobo.

[corleonee]

Thanks mate im willing to take any risks :>
The Epox rev 2.2 got a hardware limiter for 1.6v
So its possible to get around that ?
here is a guide but thats for rev 1.1 http://www.vr-zone.com/?i=242&s=1
think i need something else for rev 2.2

[corleonee]

hey gizmo i dont have a digicam mate
ya gonn help me sort this out bro ?

[Gizmo]

Since I don't have access to one of these boards myself, the only way I have of susing out the circuit is by looking at pictures of the area that needs to be modified. Without either a board or pics, I don't have enough info to be able to help. Sorry

[jnansley]

Perhaps this is similar to the 8RDA+ overcurrent mod...

This will probably only help if the system is immediately "shutting down" (CPU power off, fans/drives remain powered) at high voltages. If you set the voltage to 1.85V, and it remains at 1.6V, this could be (and probably is) the work of the BIOS.

If it immediately shuts down, then you should be looking at disabling the overvoltage protection. If it only shuts down under load, you should be looking at disabling the overcurrent protection. If it doesn't shut down at all, this is not the mechanism you should be looking at.

See if you can find the datasheet for the Vreg IC. If I'm speaking Greek, then you probably shouldn't be doing this... but read on anyhow

Located between the ATX/ATX12V connectors and the CPU socket, there should be 2 or 3 "sets" of: input capacitor(s), PWM mosfets (2), output capacitor(s), and toroidal inductor (round green thing).

There will be a mysterious extra IC in that area, that will probably be the voltage regulator. Find its datasheet, using Google, and try to determine which pin and/or resistor controls the overvoltage protection. Cut the pin or remove the resistor. This may help:

http://www.motherboardfaqs.com/article.php?31.255

I don't even own this board, so I am not exactly the best authority. You should do much research before chopping up your board.

Epox Tech could probably give you all kinds of information, in a different context, but I don't believe he will advise you to void your warranty by replying in this thread.

[corleonee]

When i select vcores higher then 1.6 it reboots and doesnt show anything on screen.
I found some pics of rev 2.2 on the net hope these help
http://www.corleone.demon.nl/pic1.jpg
http://www.corleone.demon.nl/pic2.jpg

[Aedan]

In those pictures, it looks like the PWM controller has been covered, so they're not much use in identifying the controller used.

[corleonee]

hey mate in this pic its uncovered

http://www.corleone.demon.nl/pic3.jpg

[deathstar13]

umm nice looking mobo that guy is a genius who modded it,and bet is very good looking to boot!

LOL anyhow sorry im no help as you see above ive sinked everything out for my prescott and soon to be prommy cooling.

[Clevor]

I believe all of the Prescott-compatible boards cannot run VCORE >1.60. I think the Asus boards have the same problem: won't boot >1.60. Not sure about the Abit boards.

[jnansley]

Originally Posted by corleonee

When i select vcores higher then 1.6 it reboots and doesnt show anything on screen.
I found some pics of rev 2.2 on the net hope these help

Is this at stock speed? You should try increasing the voltage at stock speed to see if the problem still occurs.

Also, to ensure that the problem isn't related to a "Prescott-safe BIOS" (some manufacturers do this due to Prescott heat/power consumption), you should also try increasing the voltage using a Northwood or Celeron.

3.7ghz is pretty fast. Things are going to get REALLY hot when you increase the voltage. How much more speed do you really think you can get? I've certainly been guilty of spending TOO MUCH time, energy, and money on cooling and motherboard modifications - to eventually get an extra 80mhz.

Just be aware that you can easily trash your mobo (and possibly CPU)... I would look around and see if people are getting higher voltages out of other motherboards, and maybe think about "trading-up" - this motherboard could probably fetch some good money on ebay, as long as it still works...

EDIT:

http://www.vr-zone.com/?i=242&s=1

"Take note that these mods are done on the Rev 1.1".

If he can get 1.88V, it looks like overvoltage protection is not the problem... at least with v1.1. The two revisions could be completely and totally different.

[corleonee]

People are getting up to 1.85 on other mobos. i ofcourse tried rasing the vcore on stock speed but its a know problem that epox rev 2.2 can only do 1.6vcore cos its designed to intel reference. :/
btw when i select 1.6 in bios i only get 1.5 in reallife so i really need this vmod.

I looked for the chip and it says:

ICS CA330954
03424
952607EF

What do i do now ?

[Aedan]

What did you use to measure your VCORE voltage? The onboard sensors (on any motherboard) tend to be less than accurate!

The chip you've found is probably the clock generator for the system, rather than the VCORE regulator. I don't believe that ICS manafacture voltage regulators - see if there are any other multilegged chips in the same sort of area. I'd expect the part to have at least 16 - 20 pins.

[corleonee]

I didn't use anything special to measure it just looked in bios
I looked for this chip marked in red

http://www.corleone.demon.nl/4PCA3.JPG

[Gizmo]

Originally Posted by corleonee

People are getting up to 1.85 on other mobos. i ofcourse tried rasing the vcore on stock speed but its a know problem that epox rev 2.2 can only do 1.6vcore cos its designed to intel reference. :/
btw when i select 1.6 in bios i only get 1.5 in reallife so i really need this vmod.

I looked for the chip and it says:

ICS CA330954
03424
952607EF

What do i do now ?

That looks like this is the ICS Programmable Timing Control Hub. This generates the clock signals and timing references for everything else on the mobo. But it isn't the PWM controller that we are looking for.

Are there any ICs on the back side of this mobo?

[Gizmo]

There is a chip in the pic above that is just below the CPU right next to the fan header. It is labled as an Attansic chip. Can you tell what the part number is on it?

[corleonee]

It's a Attansic ATXP6 0316

[Gizmo]

Well, that's not what we are looking for either. That appears to be the thermal monitor and some other junk.