Asus EAH4830 VMOD Help Please

[mattkosem]

I'd like to vmod my Asus EAH4830. I've bumped the gpu up to 1.158v via the bios so far, but would like to get a bit further. I have the soldiering skills, but don't have the resources or experience to determine which ICs are responsible for regulating the voltage on the card and the sizing for the trimmers. I have taken some pics of the backside of it. Can someone point me in the right direction? I'd like to attempt vmem and vpgu mods if possible.

Here is the half of the card:
http://img179.imageshack.us/img179/605/img0237cv0.th.jpg (http://img179.imageshack.us/my.php?image=img0237cv0.jpg)

And the other half(sorry for the glare):
http://img4.imageshack.us/img4/1804/img0238lq1.th.jpg (http://img4.imageshack.us/my.php?image=img0238lq1.jpg)

Any help would be appreciated. I can take closer pics of any helpful areas if needed.

--Matt

[Sam__]

Have you tried searching around for other peoples vmods for this card? its worth a look.

also have a read of this guide (http://www.aoaforums.com/forum/hardware-hacking/39385-diy-volt-mod-guide.html), it helped me a lot.

[mattkosem]

Yes, unfortunately this isn't a reference card so no one has done the mod on it. That's a very helpful guide. Unfortunately, I don't see any ICs with the letters HIP, SC, LM, RT, ISL or ADP on them and do not see anything on the front of the card that resembles a coil. Looking through some other vmod guides, I found that another model of card's vMEM mod attaches to a chip labeled uP6101BSA. I found one labeled uP6101BU8 on the back of mine. Since they have the same uP6101 designation, and this chip should be responsible for voltage regulation. I checked the voltage at the feedback pin (6) and found that it's .79v, and that it doesn't vary when the card jumps to its high power state so it doesn't seem like it's responsible for vGPU and seems like too low of a voltage for vmem unless it is being cut down by that point. I see 600 ohms between the feedback pin and the ground pin on it. Any ideas on other IC names to look for on the board or other possible items to look for to check voltage monitoring?

--Matt

[mattkosem]

Anyone? Are there any other guides that might get me in the right direction? Any other common part numbers. I've read through lots of vmod guides for specific cards, and that uP6101 is the only vreg on the card that I've come across on another thread. How might I find read points if I don't see chokes that have exposed coils? Should I just start probing the back of the PCB for spots that resemble the voltage that I'm looking for? If I happen to come across one, how might I correlate it to the voltage reg hardware?

--Matt

[mattkosem]

I felt that the legs of the caps on the board would be a good spot to start probing for voltage. I found that the spots marked in blue show a voltage of 1.99v when the card is in both 2D and 3D modes. This voltage seems feasible for the memory. The spots marked in green show 1.03v in 2D mode and 1.3v in 3D mode. 1.3v is a little higher than the 1.158v that I'm requesting in 3D mode, but it seems like a reasonable spot to start at for reading voltage, since they vary by the power state of the card. 1.03v is the requested 2D voltage.

Do these points give any hints to the whereabouts of the voltage hardware? The resistance I found between ground and the feedback pin on the uP6101 (which is highlighted in purple) and the vacility of it on the board leads me to believe it would be the reg for the memory on the card.

There are some larger ICs around the area that I suspect to be responsible for regulating the GPU voltage. Some have pins on 4 sides (labeled BD-AH VQK and AP-AG VQK respectively). Others have pins on 2 sides like the uP part (labeled FPJNAY V00 and LCX 74 B828 respectively). Do any of these parts sound like vregs? I'm having a hard time identifying these chips. The B828 part looks like it might be a clock generator. I cannot find anything on the others.

--Matt

[mattkosem]

I found this post (http://www.xtremesystems.org/forums/showpost.php?p=3395635&postcount=1102) about a 4850 TOP card. It appears to use the same PCB as my card. I installed the mod a few minutes ago. I'm gaming at 820mhz with 1.4v so far. I'm not sure I'll push it any further. With a requested .86v idle, I see 1.08v. With the clocks set by rivatuner I see 1.42v idle and 1.39v under atitool. Seems solid so far!

--Matt