Club3D X800XL Voltmod, succes!

[tijgert]

Hello there fella's, here's my report on the VoltMod.

I started out with a Club3D X800XL with 256MB of 2,0ns ram.
Standard the core would show artifacts at 450MHz, so I kept it at 440... but wanted more
The mem was of surprising quality and was running happily without any mods or cooling at 580MHz... I didn't hit the ceiling yet

So, the list-'o-facts:
Before the mod:

Vdd = 1.81 v
Vddq = 1.88 v
Vgpu = 1.41 v
RVdd = 1140 ohms
RVddq = 850 ohms
RVgpu = 436 ohms
RIgpu = 39.2 Kohms

After the mod:
Vdd = 1.952 v
Vddq = 1.999 v
Vgpu = 1.671 v

Below I will list only the value of the resistors that I added, you can calculate yourself what the actual resistance and Delta resistance on that spot is.

RVdd = 10.5 Kohms
RVddq = 14.45 Kohms
RVgpu = 2.29 Kohms
RIgpu = 250 Kohms

The Igpu resistor I left at 250 K because the GPU didn't crap out at 1.671 v.
Even adding the 250 K will lower the overal resistance so it nudged a little in the right direction anyway.

The pics!

Here it all begins, multimeter, tools, glasses and spare hard drives... just in case



Prepared the connectors for the resistors, so that they may be removed and installed when needed (I hate permanent solder mods).
In the top left corner you can see the WC blocks, ready for mounting when my Venice comes in .



Thos tiny little islands are too friggin... tiny!!!
But seemed to work...



Soldering to the chips was a lot easier, just hope no crap flowed under the chip...



This is how the connectors are mounted and how the resistors will be inserted into them.
You may wonder how I will keep them apart...



Well, like this! Some stripes to identify what goes where... simple as can be!



And this was the final setup.
Testing per resistor was easy, just put in little blue block, turn on pc and measure.
While the pc was on I adjusted the screw and saw the voltages change to what I wanted.




I'm sure the voltages can go higher with some fiddling and trying, but right now I'll leave it at a safe setting (at least I think it's safe ).
Benches will follow after all work is done
Until the WC and ramsinks will be installed I removed the resistors not to stress it too much, obviously I won't just leave it running with the mod 24/7 sans cooling

Oh, while you're at it, why not take a look at my WC setup!
It's at My WC project
Forgive the crappy HTML, modding is my game, not art

Questions?

The next thing I am working on is to make the mod switchable!
I had a LCD display switchable with a signal from the printerport, but it's not stable or reliable enough to try it here, but a normal switch could do the trick! (switching 3 seperate rails with 1 flick of course)... working on it

[tijgert]

Ok, mod update time

As I said earlier, I wanted to make the voltmod switchable so that the videocard wouldn't have to endure the maximum voltage 100% of the time while it's needed maybe 5% of the time.

The original design called for a 4 rail switch to switch all 4 resistors simultaneously
I also wanted to make the mod switch off, regardless of the mod-switch position, if I would set the fans to low (7v).

So I took away the complicated 4 rail switch and I added a relais to the design, in series with a more simple 'master' switch, the fan switch and a little blue led to tell if it's working or not (and because blue leds are cool )

The mod was also designed to be added on top of the existing mod.
I refused to tamper with the installed mod to avoid breaking the solder and in case my mod-switching-setup not function as intended, I wanted to be able to just take it out and toss it into the corner without having to fix the old mod first.

As you can see in the first picture, I used two smaller relais instead of a single big one because I didn't want to stretch 8 wires all across the case and a bigger single relais wouldn't find enough grip on the video card.
I mounted them on the edges to avoid any interference from the field the coil generates so close the contacts. (it may be small, but can still interefere)



You may notice that it's now fully shrink tubed



Here you see the complete circuit.
The yellow lines indicate the fan switch wires that I didn't solder back yet (I lengthened them while I was working on it anyway).
The other side of the fan switch switches 12v to the led and on to the second switch, the mod switch.
From there it goes to the relais and back to close the circuit.



This is what the installed modded-mod looks like.
You may see a few changes on the final model compared to the previous pictures.
The two relais are now parallel as opposed to series because the voltage drop in series was too much to make them switch AND have a bright blue led in series as well.
Also the idiot at the hardware store was wrong about which pin was the common on the relais, so I had to resolder some of them.



The front view with the fan switch on theright and the mod switch on the left.
The mod is now switched off.



That's about it for now.
No benches yet, my Venice should come in very soon now and once that baby is installed I'll hook up the water cooling and a benchin' we will go!

[Holst]

Very nicely done.

I like the way you used the relay to turn the mods on and off, a clever idea.

You might want to put a diode backwards over the relay coils, just in case you get a spike when switching.

Very neat job.

I hope you get good clocks out of it.

[tijgert]

Well, I did put a Light Emitting DIODE in series with the relais
Or did you mean something else?

[n00b 0f l337]

Your pics only show 3 of the 4 spots where you did the vmods. Your works pretty insane, but could you get a pic of that 4 spot? My cards stuck at 455/555 watercooled, no cooling on ram, and it needs a vmod for sure.

[tijgert]

I assume it's because you want to see for sure where to solder the resistor?

Well, this is the pic I used:



It's obviously the 20k resistor to the right, on the empty solder pads.

[n00b 0f l337]

K thanks. This will be my very first vmod's so I'm making sure I dont f anything up.

[DarkManX_BG]

I have one more question - how much did it help overclocks?
Also, why are you still using stock cooling? It sucks on the Club-3D, mine got as hot as 79C under heavy load

[n00b 0f l337]

Also, where did you get those VR's? And did they fit the 3 pin fan plug's perfectly? I love that mod idea.

[[XC] moddolicous]

wow, really nice job. Get that under some really nice cooling.

[XiN]

Wow, great work!

I have the same card, but under Zalman VF700 ... do you think that 1.5 volt (for gpu) is too much for air cooling?

[DarkManX_BG]

Wow, great work!

I have the same card, but under Zalman VF700 ... do you think that 1.5 volt (for gpu) is too much for air cooling?

He has it running at 1.67V with stock cooling, so I guess a VF700 will be fine untill at least 1.75C

[XiN]

He has it running at 1.67V with stock cooling, so I guess a VF700 will be fine untill at least 1.75C

Ops, I have missed that particular

Anyway I have fear to pump up too much voltage, I'll start with 1.65

[tijgert]

As promised, some benches of my OC'd X800XL.

First the hardware setup:
Mem - 205MHz DDR @ 2-2-2-5 1T Trc = 10 + Trfc = 14
CPU - 2660MHz A64 Venice @ 313HTTx8.5
Mobo - MSI K8N Plat. (Neo4 Ultra)
CPU + GPU H2O'd (homemade yummy goodness).

The voltages have been cranked up just a bit.
Vcore = 1.73v, Vddq = 2.02v and Vdd = 2.00v

Core/mem 500MHz / 600MHz (yeah, not bad eh?)
3DMark 2000 = 26253 marks
3DMark 2001 = 26626 marks
3DMark 2003 = 12490 marks
3DMark 2005 = 5912 marks

The core@510 freezes after a few secs, 505 might work but I like to keep some buffer.
The mem@600 is artifact free, but only at core=500MHZ. At 400MHz core the mem@600 does give some artifacts... dunno why.

I kick the X800XT's ass just looking at the stock clocks, but comparing scores in 05 I even slap the X800XT PE's behind! (if the chart I looked at was correct).
Mind you, overclock those other cards and I'm right back on the end again.

Stock it did 440/580 and I didn't check if 580 was the ceiling.
Now it's +60/+20 compared to non modded and +100/+110 on stock.

All in all, not bad

Edit:
At 505/605 (roughly a 1% increase in speeds) I get only 10 marks extra.
10 on top of 5912 is 1.7% extra performance... where did the rest go? I'm guessing a bottleneck somewhere else than the videocard.
Perhaps a 2660MHz Venice just isn't powerfull enough...

[5-Clicks]

very clean looking and great voltages! keep up the good work!