Benchmarks going down...?

[henzo]

I have had a decent 3DMark06 score (see sig) @my 8800Gt's oc (also see sig). BUT, when I upped the cards oc to 726/1746/1042, my score is actually dropping down to around 10.5k 3dMark score. That seems to be a big drop coming from an 11123 score with alot bigger oc. The oc shows no artifacts in ATITool and doesnt fail the fur testing either. It games a little better in every game I play except Assassin's Creed. In this strange instance, the game twitches and goes into a sort of 2x speed mode at some points and I get a lagging sensation in spots even though it is a single player game. All my specs are in the sig for the rig I game on so any expert ( or not lol ) help would help me get this wierd phenemina understood weould be greatly appreaciated.

Here is a GPU-Z validation link for ya to see what else could be wrong. http://www.techpowerup.com/gpuz/n5hkq/

RivaTuner's hardware monitor says my clocks are actually a small bit higher than what GPU-Z says ( 729/1753/1051 ) for whatever thats worth.

[JamesXP]

It sounds like an unstable oc or lack of power.

What brand is your PSU?

[henzo]

It sounds like an unstable oc or lack of power.

What brand is your PSU?


The oc is stable from all of the tools and games I play, except the wierdness that I get with Assissan's Creed like I said.

My PSU is a generic 550w unit. I only comsume 442w according to a psu calculator that I found in the cases and psu portion of this forum.

[JamesXP]

I'm betting your 'generic' PSU is your probablem.


It will never output 550w, I guarentee that :)

[henzo]

Is this a good PSU? I really cant afford to buy a Corsair or a Galaxy right now. I do have the money for another 8800GT to run in sli and oc them both. Will this PSU be able to handle both of the cards with an oc on them along with my cpu oc as well?

http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=2974472&CatId=2496

[Anubis_386]

I just ran your system through the Power Supply calculator (full version, I bought a lifetime licence) and it said for your system (with another 8800GT) needs 515W with 35A ... So I wouldn't think that PSU would cope .. Try and find one that puts out ~40-45A on the 12v rails.

[JamesXP]

http://www.buy.com/prod/corsair-tx-650w-atx12v-power-supply/q/loc/101/206178324.html


It's a corsair, and it's cheaper than the ultra.

[henzo]

Thanks for the link. That one should handle 2 8800GT's pretty well right?

[JamesXP]

Correct.

[henzo]

Thank you sir, much appreciated. Do you, or anyone else, happen to know why Assassin's Creed or any other game would run in a sort of 2x speed at all and lag out as a single player game? Seems wierd, been gaming for many, many years and never seen that before lol.

[Shadowmonk]

100% sure its your PSU, i run PCPnC 750 and have no trouble pulling down 690w, you generic PSU prolly has 3-12v rails and cant pump the amps.

[Tweaked!]

The last article at the bottom of the page (http://www.pcpower.com/technology/myths/) will sort of explain why most power supplies can't handle the loads demanded by video cards like the 8800s and 9800s. The 8800gts averages a draw of 28a, and a lot of the more current power supplies tout multiple 12v rails, each ranginf around 15 - 18a. That is not enough to power one of these cards much less two. There are very few manufacturers out there that are supplying large single 12v rails, the Corsair and the PC P&C are the dominant manufacturers right now that do.

Give those articles a read and you'll get a much better understanding of what we're refering to. :cool:

[JamesXP]

The 8800GTS draws 336W? that's new to me damn...


Also shadow it is not because of how many rails there is, it is because the PSU is badly made and extermely overated.

[tRidiot]

28A AVERAGE for an 8800GTS? I'm having trouble with that one.... as my Silverstone has only 35A on the 12V rail, I don't know how I could possibly be running my 8800GTX and my Q6600 OC'd to 3.4 at the same time, with 3 HDDs and I dunno, about 5 120mm fans.

Just seems odd to me, as I'm having NO power problems at all.

[henzo]

@Tweaked! That makes sense to me. I was wondering if buying a multi-rail rather than a single-rail would be better, after that, i'm gonna get a nice corsair so I dont have to worry about that in the future. I am thinking about dropping a little more coin on a nice 850w or better psu. Thank you for help everyone.

[jason4207]

Maybe 28A for the entire rig...

[Tweaked!]

28A AVERAGE for an 8800GTS? I'm having trouble with that one.... as my Silverstone has only 35A on the 12V rail, I don't know how I could possibly be running my 8800GTX and my Q6600 OC'd to 3.4 at the same time, with 3 HDDs and I dunno, about 5 120mm fans.

Just seems odd to me, as I'm having NO power problems at all.

I just figured that out yesterday as well. See in my specs I'm still running a OCZ GameXstream 700w and thought I was fine, but I was experiencing random reboots while playing intense games (crysis, cod4, etc...) and was figuring it to be associated with my o/c. So I finally read some of those articles as well as some other reading material about psus over at johnnygurus and a few others and started to realize that my psu was my problem. Here's a listing for one 8800gts at newegg (http://www.newegg.com/Product/Product.aspx?Item=N82E16814130299) that shows it requires a power supply that can feed it 26a (look in the specs).

So for me, I just ordered a Corsair tx650w and a PC P&C 610w yesterday (got both my wifes and my rig setup the same with the same psus and video cards). Buy.com has the Corsair for 69.99 after a $20.00 MIR and a $10 off for using Google checkout for the first time. Otherwise I would've probably just ordered two of the PC P&Cs. Everything I've read about the Corsairs though make them seem as if they can hold their own against PC P&C. :cool:

[JamesXP]

They can.


The Silencer use the same OEM as The HX520 HX620 VX450 and the TX650 AFAIK.