Got my 2900pro.. Oh no! no 8 pin!!

[Jakalwarrior]

My PSU has an 8pin connector that looks like a PCIE connector.... but... it wont fit. The card came with a bunch of adapaters to make 6 pin connetors but no adapters to make an 8 pin. Does the lack of adapter hurt the OC potential? Should I bother buying a 6 to 8 pin adapter?

Also are there any programs to up the voltage other than ATI tool? Because ATI tool doesnt seem to want to work on my M3A motherboard.

Also just wanted to say... ZOMG this card is friggen huge. Had to bend part of my case to make the dual slot part fit and had to rework my wire management to make room for the length.

[Jowy Atreides]

My PSU has an 8pin connector that looks like a PCIE connector.... but... it wont fit. The card came with a bunch of adapaters to make 6 pin connetors but no adapters to make an 8 pin. Does the lack of adapter hurt the OC potential? Should I bother buying a 6 to 8 pin adapter?

Also are there any programs to up the voltage other than ATI tool? Because ATI tool doesnt seem to want to work on my M3A motherboard.

Also just wanted to say... ZOMG this card is friggen huge. Had to bend part of my case to make the dual slot part fit and had to rework my wire management to make room for the length.


iirc the 8 pin is for an overclocking feature,

and the card runs stock ok with 6 pins

[Jakalwarrior]

I have no intention of running stock ;)

[WrigleyVillain]

iirc the 8 pin is for an overclocking feature,


Yes it is but only for overclocking with ATI's Overdrive in CCC. Can overclock just fine with just 2 6-pin connectors using Riva Tuner or AMD GPU Tool.

Yes ATI Tool is presently the only util for adjusting voltage. Other option is to flash w custom BIOS. Info in the (long) 2900 Pro Owners Thread (http://www.xtremesystems.org/forums/showthread.php?t=160458&highlight=2900+pro+owners+thread)

[Jakalwarrior]

Do they overclock better with the 8 pin ones though? Is there any real reason CCC locks out the overclocking? or is it some some sort of "test" to see if you have an enthusiast PSU before letting you push further?

Honestly im not used to running any PSUs past 50% draw for any extended period of time. Im actually a little nervous with this little 650 watt that has ~57amps on the 12volt lines. Though with my chip at only 1.3vcore and only 2 hard drive maybe it wont be that bad.

[p0tter]

http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=186&products_id=21721

*** NEW *** 6-Pin PCI Express to 8-Pin PCI Express 2 Adapter Cable - Sleeved

[WrigleyVillain]

Do they overclock better with the 8 pin ones though?

I wondered the same thing and the answer appears to be no. That being said, I never received a good answer as to why the 8-pin is needed at all for CCC oc, not that one isn't out there.

Go ahead and buy the adapter and test, I'd be curious to see your results.

The main thing that helps them oc better in general is the usual-more voltage.

My stock vdcc is 1.15 with (crap) stock cooling and I am stable up to 825 core. Some folks have higher vdcc and/or a modded bios and have benched 980+ with around 1.35v. Nickless, Truckchase and Martin.v.r in the 2900 pro Owners thread come to mind offhand. See this post (http://www.xtremesystems.org/forums/showpost.php?p=2726963&postcount=1056) for example.

And I run my 2900 Pro just fine with an OCZ Powerstream 520.

[alexio]

I wondered the same thing and the answer appears to be no. That being said, I never received a good answer as to why the 8-pin is needed at all for CCC oc, not that one isn't out there.

ATI presumes that the avarage PSU with an 8-pin PCIe connector is more powerful than hose without. It's just a precaution to stop people from overclocking the cards that don't know what they are doing ;)

[Jakalwarrior]

Im going to keep the stock cooling and just hope I break 800 so I can pretend I bought a hot powerhungry 3870. If you guys in general arent seeing any advantage to the 8 pin im not going to blow ~10 bucks getting one just to have it as more case clutter :/

[WrigleyVillain]

The 3870 draws a lot less power than a 2900 but doesn't run that much cooler it seems. The stock cooling on the 2900 isn't terrible just not really good like some after market solutions. The fan doesn't ramp up from the default 37% until the card is in the 90s iirc so if you don't mind the noise you can use Riva Tuner to run it faster or customize to your liking.

[Jakalwarrior]

Now if only ATI tool worked with this motherboard, or if I could see my temperatures, or control my fan better, etc... :(

[xMrBunglex]

the 8-pin connector is a bad joke. it just has two extra ground wires on it - they don't do anything at all. but Overdrive is locked if you don't have one.

the 3870's don't run as hot as the 2900's when you think about it. they're both just designed to run silent until they hit 90°. the 3870's heatsink isn't nearly as good as the 2900's but i can keep my GPU's to 63° with my fanfix BIOS. all you need is a little fan speed to keep it cool. the 2900's have better cooling solutions though.

to the OP, i'd recommend a modded BIOS. it's the easiest way to go. i assume you can find one that has a built-in overclock and tweaked fanspeed profile.

[Jakalwarrior]

I dunno, flashing any kind of bios always feels like a slight gamble to me.
Anywho atm im sitting at 850/1000 though I dont really have a way to tell if its stable other than RTHDRIBL which ive been running for about 10 mins. Waiting on 3dmark06 to finish downloading.

[Jakalwarrior]

Rather than fiddle with it i have left the settings at 800/900. It will go a bit higher but waiting through 3dmark to find out is giving me a headache, and my scores aren't really going up all that much. 800/900 only gives me a score of 9553.

[l3fty]

For lack of an 8pin connector. You could try this. http://www.xtremesystems.org/forums/showthread.php?p=2230258#post2230258

For more info on 8pin connector's their layout and if they're really needed. This thread has alot of info in it.
http://forums.techpowerup.com/showthread.php?t=31069

The link WrigleyVillain posted initialy is a good one too.