Project: 3 Course Meal

[stocky]

Brilliant!

I always look forward to your projects Kenny!

Would like to see some shots with it all operating, as I see a block and phase unit not in use

 

[Bradmax57]

Good stuff Beer Kegs are great

 

[K404]

Decided to change 3CM a bit into a slightly lower-fat option...







http://img453.imageshack.us/my.php?image=3cmlowfat4qr9.jpg

 

[K404]

The CPU water loop is also now propped up on 2 small boxes, and the I/O cables run between them.

 

[K404]

 

[sacha35]

Looks very good mate any more pics to view as there is a lot in the way that makes it hard to see all.

Nice work though mate, it turned out good.

 

[stocky]

There's definitely a lot going on there! What GPU is that with the V-Mods?

 

[K404]

Its a 7900GS Its an OC version so stock clock is 500/520 (Delta)

With a little persuasion it'll bench at 740/760 (Delta) on water Dice pot contact was poo so didnt get higher

Will get some more pics up this afternoon

Cheers!

 

[K404]

This might be really sad but the voltmod for the core is a bit more interesting than most..

The cards have an OVP feature based on VID. Its roughly 0.1V above the default VID, although its possibly temperature related. To overvolt the card properly, you need to be able to mod the VID as well. There is a 2^3 VID table for the IC, and VID is derived from a binary code. The logic levels are 0 or 1 (as in all binary) which correspond to certain pins being set to ground or 5V. To adjust between the default (1.2V) and 1.3, 1.4 or 1.5V VID, its lucky that a relevant pin only needs to be grounded instead to connected to 5V. Thats what the 4-pin jumper is for. I use jumpers (same kind as CMOS clear jumper) to connect whichever grounded pins I want, or I can leave all the pins off for default VID.

Once that is done, then I added the usual voltmod to control VCore on the fly.

 

[stocky]

lol at the straws holding it all up!

 

[Thickbrit]

Clever work with the ovp mod mate and i love the whole ghetto/get at approach you've used.

 

[bazx]

very clean setup kenny

where are you getting all the info for the vmods

or do you study this type of work

 

[maverik-sg1]

Question on OVP on these cards - does it effect both the GTX and the ultra, or even the GTS?

In respect of overcoming the OVP and use of more volts - what is it worth in terms of Mhz?

 

[K404]

Clocking + volting G80 is a different beast altogether

On the 7900GS... the right voltmods add 100MHz core EASILY- I wasnt getting much past 600MHz core on stock VID, if I got to 600MHz at all. Will confirm that later though.

You know the benefits that voltmods bring, you've been using them long enough!!

From my GTS640 days- I got 650MHz core stock cooler, 715MHz stock voltage at zero degrees load, and 740MHz voltmodded under water.

 

[K404]

very clean setup kenny

where are you getting all the info for the vmods

or do you study this type of work

Im an electronics engineer, but a lot of the hints come from XS/VR-Z.

 

[maverik-sg1]

Clocking + volting G80 is a different beast altogether

On the 7900GS... the right voltmods add 100MHz core EASILY- I wasnt getting much past 600MHz core on stock VID, if I got to 600MHz at all. Will confirm that later though.

You know the benefits that voltmods bring, you've been using them long enough!!

From my GTS640 days- I got 650MHz core stock cooler, 715MHz stock voltage at zero degrees load, and 740MHz voltmodded under water.

I did read all that in previous posts mate and clearly I hvae my own expierence with VM'd kit - but this is the first time I saw ure mods here and wondered if most other volt mods include (or need) the OVP bypass on other G80 that are non ultra - to put another way, do the GTS and GTX require or benefit the same OVP Bypass for the mods to give tangible or even better results.

Or to put another way - what clocks over max stock or normal volt mod can be expected with or without the OVP?

An example of what the answer would look like and be clear:

Card 8800GTS 640mb

Stock = 650mhz

VMod = 700mhz

VMod with OVP ByPass = 750mhz

You might know (or guessed from the above) I am not an electrical engineer so the example of the answer required above, replaced by hard data from your experience, would be an easy way for us non electrical minded peeps to understand.

Apologies if I misdirected you with the way I originally asked the question, hope this is okay?

Cheers

Mav

 

[K404]

I *think* the 8800 series has OVP, but its high enough that you'll never use those voltages unless you're running -100 odd, and maybe even then it wont be a good idea. Droop is a bigger worry on the G80 cards, especially the GTX/ Ultra. Not sure if theres a fix for that..