700mhz wall on HD4850 is smashed.

[jimmyz]

awesome results guys, great to see "the little card that could" kicking arse and taking names, these things are nice.

[Jaystar]

So an Arctic Cooling Accelero S1 + wire ties + yate = win !

Do you think these http://www.svc.com/gt-ram-kit.html combined with the sinks from the s1 kit will be enough to cover the pwm area.

[jimmyz]

So an Arctic Cooling Accelero S1 + wire ties + yate = win !

Do you think these http://www.svc.com/gt-ram-kit.html combined with the sinks from the s1 kit will be enough to cover the pwm area.

there is lots of room there so I guess yes but I don't use the cooler you mention so Ican't say for sure. mine has a few old Zalman blue VGA sinks and never gets very hot. Ram is naked btw I like my ram like my ladies naked all the time. the chips feel very cool and my clocks seem better without the factory cooler which covered them.

[vinteg]

gurusan. i just flashed your bios. all went well. problem is however that i cant turn off that frigin overdrive in CCC. i click apply and it just enables itself again. any idea on this problem?
srry if it was allready asked.

edit1: well bios sucks for me arti's all over the place. dont realy understand since temp stays at like 65°. i can imagine the core being more oc'able on one card other than mine but the mem should be around the same, no?

[JamesBong420]

@gurusan....

so u were actually 950 stable at under 1.5v?
i have to put 1.52v(load) for even 910mhz...

[biftek.]

Whats the max safe voltage for the ram?
I'm at 2.2. Thinking it's a bit overkill though looking at Guru results...

[jimmyz]

Whats the max safe voltage for the ram?
I'm at 2.2. Thinking it's a bit overkill though looking at Guru results...

general rule would be 10% so 2.2 personally I don't oc the ram too much as they generally don't help the performance much compared to the risk of death.

[biftek.]

general rule would be 10% so 2.2 personally I don't oc the ram too much as they generally don't help the performance much compared to the risk of death.

Awesome thanks for the quick reply, lowered it to 2.11V
Now time to OC it

[tvdang7]

any visiontek ppl on here?

my stock voltage overclocks suck 675/1060. seems like every other vendor does 700/1100 + right out of the box.

btw whats the default 3d voltage?

[Bitgod]

Gah, wish I knew why my Crysis is jacked up, I'm getting worse numbers when doing 4850 CF than if I disable CF. COD4 is fine though, getting twice the FPS my 8800GTX did.

[XMoA]

@gurusan....

so u were actually 950 stable at under 1.5v?
i have to put 1.52v(load) for even 910mhz...

yeah but he's using liquid cooling :P

[Confused_User]

any visiontek ppl on here?

my stock voltage overclocks suck 675/1060. seems like every other vendor does 700/1100 + right out of the box.

btw whats the default 3d voltage?

i was getting bad clocks on my visiontek as well, worse than yours 670/1025.

when i flashed to the latest msi bios (160/500 2d clocks) i was able to overlock to 720/1075 100% everyday stable

[gurusan]

@gurusan....

so u were actually 950 stable at under 1.5v?
i have to put 1.52v(load) for even 910mhz...

I thought so but then it crashed after about an hour of gaming. But I am stable 910mhz 1.45v

[Rattle]

So an Arctic Cooling Accelero S1 + wire ties + yate = win !

Do you think these http://www.svc.com/gt-ram-kit.html combined with the sinks from the s1 kit will be enough to cover the pwm area.

the s1 rev2 ramsinks are the only thing you can use out of it, there's no pwm sinks that work, that thermalright sink set will be perfect for one card though.
Thats basically what i used left over thermalrights and some others I had laying around. I would grab 2 sets of spared though.

[Jaystar]

Thanks for the input guys. I agree you can never have enought ramsinks around. So two pwm sets it is.

On the subject of vram I bet the stock heatsink does heat that stuff up a good bit, but you get 8 litte ramsinks free with the s1. So I figure why not cover them.

Now these cards are pretty much built on the same 55nm process as the 3850 and 3870. So the chips should be able to tollerate similar voltages 24/7. Anyone have a volt modded 38xx series card still chugging away? If so how many volts were you applying. I still miss my 2900pro in that regard man she loved volts

[gurusan]

i put about 1.45v through my 3850 every day since december 07 with no problems. SHe's for sale now too

[Jaystar]

i was getting bad clocks on my visiontek as well, worse than yours 670/1025.

when i flashed to the latest msi bios (160/500 2d clocks) i was able to overlock to 720/1075 100% everyday stable

The bios might have given you a little voltage boost. 1.16 -~> 1.21. I have a running theroy that this voltage was ment for overdrive but just doesnt work correctly on some bios. The only way you are going to find out is with a dmm. What I did was connected some test clips to the vgpu point and ground, and have the dmm sitting right on the table next to me.

The pwm on these cards doesnt seem that bad really. Under load my drop never exceeds .015v. I have no way of telling how clean the output is, but if a cap mod diden't allow for a higher oc we can assume its clean enought.

[gurusan]

Which caps would we go about replacing?

[tvdang7]

i was getting bad clocks on my visiontek as well, worse than yours 670/1025.

when i flashed to the latest msi bios (160/500 2d clocks) i was able to overlock to 720/1075 100% everyday stable

wow so we can flash with other vender's bios's?

how come in the details both bios's say the same voltage.
http://www.techpowerup.com/vgabios/1...12.080605.html
http://www.techpowerup.com/vgabios/1...12.080523.html

[jimmyz]

wow so we can flash with other vender's bios's?

how come in the details both bios's say the same voltage.
http://www.techpowerup.com/vgabios/1...12.080605.html
http://www.techpowerup.com/vgabios/1...12.080523.html

All 4850's so far are reference design and made by Sapphire AFIAK. so bios's are interchangable as long as memory type and brand are the same.

just as all CPU's have a range of VID values so do GPU's, not all chips demand the same voltage to remain stable. I measured my cards with a mm, the first goes to 1.21v under load, the second goes to only 1.16v under the same conditions.

[JamesBong420]

Which caps would we go about replacing?

just look at the caps and then u can make your decision... and i didn't replace caps i just added on the back.... the 2.5v uf820..

@xmoA
that is not why at all... i tossed a loop on mine and it didn't get an higher oc then my s1.. same with my 3850... only way i could get passed 1039mhz was to toss my water chiller on it.. they are not hot chips..

[tvdang7]

Just flashed my visiontek with the msi bios that was provided a few pages back. Everything works great except the 2d clocks. its staying at full blast.

[zbomb5610]

any visiontek ppl on here?

my stock voltage overclocks suck 675/1060. seems like every other vendor does 700/1100 + right out of the box.

btw whats the default 3d voltage?

my visiontek with just the bios modded does 750/1150 stable. my cousin also has one and his does 740/1150 as well. Maybe we just got lucky on the cards we got.

i might try to do a pencil mod for the vgpu so that i can try to hit around 850 if possible, that would be sweet.

[Freaky]

my visiontek with just the bios modded does 750/1150 stable. my cousin also has one and his does 740/1150 as well. Maybe we just got lucky on the cards we got.

i might try to do a pencil mod for the vgpu so that i can try to hit around 850 if possible, that would be sweet.

Which one ? Guru's modded MSI BIOS ?

[D749]

any visiontek ppl on here?

my stock voltage overclocks suck 675/1060. seems like every other vendor does 700/1100 + right out of the box.

btw whats the default 3d voltage?

One thing to consider is what people consider stable. I'm able to push my VisionTek cards pretty high on stock voltage but it's only until I leave FurMark running that they will blow up. Games, 3DMark, etc. are all fine. Want to check stability? Fire up FurMark, set it to 1920x1200 full screen, and let it run awhile.