7900gt 512mb 800/1000 on air...

Ok, I used the fan mod on the fan for the NV5 cooler, black on black, red on yellow and am still trying to find out rpm's but, I just hit 800/1000 w/powerstrip and temps won't go over 68c using the HDR program at 1440x900:arnie: . Before temps would climb over 70 and hit 77 with the alarm buzzing at 700/850. How far can a gt go? I saw on vr-zone 745/915 and even 800/1063 with a 1.7v mod...I have done this with no mod at all!:hatty: My second gt is in the mail and should be here this week, hope it goes as far. Is this safe to do? No artefacts, temps below 70 (yellow colored on NVTemplogger). My only convern is how long will the fan last like this...I'll try some benchmarks next.

 

Nope, fan burned out after about an hour, got it to go again at regular speed so I'm not gonna push my luck. 3dmrk 06 froze midway through the proxicon test, great. I'm gonna order some high cfm fans to see if i can mod the cooler with those and not have to toast the fans...

 

Yea there is a reason its a +5V fan and not +12V... dont try it it will burn out unless its like a fan on the Zalman coolers which explicitly says in the documentation and on the fan that it runs at +12V and +5V. Apparently you dont care about noise... if you do I recommend an adjustable speed fan, the knob is usually attached to a PCI slot. I have one of those in my comp right now.

 

The noise was just temporary to see how far the card could go. I did order some 92mm adjustable fans and will try a mod soon. Not now though, my first 3dm06 score was ovre 8k in sli today so stock speeds will be plenty for now. Maybe H2o down the road.

 

Wow... 800/1000 is INSANE!

 

The cards run at 1.45v asccording to the bios.

 

:O .... 800/1000 ??? OMFG .. did u actually complete a benchmark with those clocks ??? Results ??

 

Wow... That's a nice O/C for that card!

 

Nope...

I was tweaking in powerstrip to see how far I could go, I think it went to 800-1000 with rthdribl running w/no artifacts and I was monitoring gpu speeds with NVMonitor. When I went to vr-zone to see what they hit for speeds the temps shot up quick, the fan lasted about 15 minutes then slowed to almost a stop. While the fan was running though temps were at or below 68c. I ordered 2 variable speed fans from newegg but the nv5 fans spin backwards so these dont work, they are 73 cfm fans. I'm still trying to work on a cooling mod for these cards that will be equal to the nv5 at 12v, or find a way to get the fans to go backwards. I think if I flip the magnets inside they will turn the other way, hard to do without breaking something. I also ordered some cpu heatsinks to try and mod those to fit like in the sticky here, I got some flatter ones so I cold sli still. Any ideas for modding a fan motor to spin backwards?

 

You mean you want it to sping the opposite direction? It's DC so you should be able to reverse the fan wires... I would test it on a power supply first though...

 

Tried it, didn't work.

 

The only other way I could thing of would be to do a 180 on the shaft. But like you said about the magnets, could get tricky...

what about fliping the fan blades over? In other words take it off the shaft and flip it 180, then back on...

 

hey j_blaze, are you in new zealand?

 

Here is the vr-zone mod mentioned:
http://sg.vr-zone.com/?i=3437&s=4

Incredible that you did this without and vold increases.

 

OK, I'm running out of fans to break, I have a couple cpu heatsink+fan coming this week. They are all copper. I hope if I overvolt the fans they should keep the cards pretty cool. And they are low profile so I should be able to do both cards and keep sli.

http://www.newegg.com/Product/Product.asp?Item=N82E16835150029

The third reviewer actually moded these for his vid card already. Older cards though.

 

Would love to see some single card benchmarks, blaze.

 

..the fans on the NV5 won't run at 12v anymore, they slow down to almost stop. I have some 12v fans that spin at 4000rpm but cant find a way to make them spin backwards. I'm almost going to go H20 soon if I can't figue this out soon.

 

Oh, Boy...

Now the NV5 fan is fried, I had to mod the coolers again, this time to use the other fans instead. Not bad, I had to cut out the whole motor assembly from the NV5 and glue in the motor from the new fans. I went ahead and did the 17v overvolt mod and the fans run fast. (the speed control on them is about half) Temps are now 70 max with rthdribl at 800-1000, but after some serious artefacts in proxicon, 3dmark06 just crashes at the beggining of firefly forest and I get a message that nv4something.??? had to shut down...maybe a bios flash next? I am assuming the rthdribl program is not an accurate test of card temp and stability, even for 30 minutes. At least I can do 700-850 super stable 8929 3dmark06.

 

Dude, for all that work you are putting into those fans, I would have went liquid cooling long ago...

 

I'll probably go H2O next upgrade, maybe cpu or dx10 early next year. Depends on how crysis runs on this baby. I'm looking around to see how to flash my bios and see if that changes oc stability for these. I need a small H2O setup cause I have a mid tower and theres barely room in there, and I don't want anything external.