4600 vmem mod

[Tekime]

I finally performed the vmem mod on my card. It's a MSI geForce4 Ti-4600. I was going to do SMD grabber mod a while ago, but they were just too big to have hanging off my card, although I'm still too scared to solder this thing

So I pulled the metal grabber out of two SMD's and used heat shrink tubing to secure the resistor. Also tried using it to keep the hook flush on the pins, but it was not as easy as I thought. This was a 1Kohm 1/2W resistor.

It's pretty ghetto, but it's smaller than the grabbers and easier than soldering:



I managed 760MHz memory vs. 742MHz I had without the mod. Not a huge jump, but it's running a bit smoother in BF1942 with details up. Actually it would run fine at 764/768 but with minor artifacting.

A few questions after doing this mod though:

1. Would some hot glue work okay for securing the grabbers?
2. How could I remove the hot glue if I decide to solder?
3. How can I check vmem with a multimeter?
4. What is the max safe voltage you would recommend? No W/C, just Tweakmonsters and fair case cooling.

Thanks

[talldude]

Hot glue is over 200C when it leaves the gun. You'd run a SERIOUS risk of damaging the card. I'd secure it with some silicone since it doesn't come out hot and it's removable in case you want to solder, although I don't see a reason to do that.

[Tekime]

I've seen a couple of people doing hot-glue vdd and vmem mods, are they using something different then?

I made a trip to Radio Shack today and found some nice micro-clip test jumpers. I hope these work because they are much smaller than the test clips I had. I also picked up a 1Kohm trimmer, and I think I'll just use that.

[vertices]

You can use hot glue with no probs.

[vertices]

Here ya go for measuring points.

[Tekime]

Thanks vertices. I think I need to ditch my old analog multimeter though, it's a) analog and b) has like 3 settings. Guess it's another trip to Radio Shack tomorrow.

Any ideas on how I could get a digital display and have it show my voltage without using a multimeter?

[vertices]

Not really, everyone, including myself, just uses a digital multimeter to measure these voltages.

[Tekime]

Yeah having a little screen would be incredibly handy though for on-the-fly OC'ing, especially being able to actively monitor volts while turning the trimmer.

Anyway, I got a new multimeter today. And I'm totally confused now.

I thought the Ti4600 default mem voltage was 2.8v. Testing with the multi I'm consistently getting ~2.795 which is basically 2.8. It's as if I never did the mod, but after the mod I got 18MHz I could never get before.

I guess it's time to remove the old mod anyway, and I'll test it then. Strange I tell you.... any ideas?

edit: Oh, and I'm taking the volts from here (note the small colored circles):

[bigpoppapumpg]

Originally posted by Tekime
Thanks vertices. I think I need to ditch my old analog multimeter though, it's a) analog and b) has like 3 settings. Guess it's another trip to Radio Shack tomorrow.

Any ideas on how I could get a digital display and have it show my voltage without using a multimeter?

Yuppers, osciloscope! A bit more money than a multimeter though

[vertices]

A better way to do the mod is either to take the lead from the 3rd leg of the IC and ground it to the screw that holds the card in (which would allow you to take the ground off thus disabling the mod).

Or to put a small switch inline so you can turn the mod off.

Also, I always use multi turn pots instead of regular resistors, this way you can fine tune your voltage.

Also, if you solder wires coming off the measuring points, like in the picture, you can attach your multimeter to the wires and have hands free ability to watch the voltage. This way you can use your hands to turn the pot while watching your voltage.

Pots are much better to use that straight up resistors.

Also, you are measuring in the correct place.

[Tekime]

Thanks again. I did get a pot (1Kohm 3/4 watt VR) which I'm going to use. I'm not ready to solder it yet, but Grounding to the screw is a good idea. So If I remove the ground I won't harm anything, just disable the mod?

Grr.. I wanted to do this last night but I didn't get back in until like 2am :| I won't be soldering just yet but when I do I will probably add those wires for voltage monitoring. I really hope I can get this card up another 20MHz or so, I think I'll be able to kick my details up one more level. I can't stand a single shred of lag in BF1942, and I'm nearly there..

[Tekime]

HELP!

Redid mod with a VR and micro-clips. Voltage is reading correctly now @ 2.984 with the trimmer at full resistance. I can only get 748MHz on mem though, so I think I was doing something wrong with my previous mod. I suspect the previous mod was ineffective (maybe not grounded?), and RivaTuner was interfering with the Coolbits reghack somehow. I don't know what else would explain the 760MHz clock I had when it was reading stock volts

Anyway here's the new mod, much cleaner:





I've increased voltage up to 3.1V and I still can't break 748Mhz. Should I go higher or do you think this is the limit for my vram? It starts artifacting at 748MHz with 2.984 OR 3.1V, it makes basically no difference...

[vertices]

Hmmm....I don't know man. You have definitely increased your voltage though if it is reading correctly now on your multi.

I don't know. You always hit a wall where more voltage does not help, but usually you would see some sort of increase on the speed of the RAM with this mod. Unfortuneately, I don't know what to tell you besides keep experimenting with it.

[Tekime]

I'm thinking about formatting and reinstalling 2K... I'm not sure if it would help but considering how weird Coolbits was acting before, it might help. Hoping I didn't hurt my card. Might pull the mod off and re-test at stock volts to start fresh.

How high is too high on vmem, any idea? Think 3.25 will start a small fire?