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SirJpg
06-14-04, 05:00 AM
I have a 5900Nu ( 400/850) and I have flashed it to a 5950U ( 475/950 )
Recently, I have discovered that I can overclock more the gpu if I lower the mem speed...so here comes my question: in this card what is more important? the core or the bandwith? ( With coobits2 I can push more than 535 mhz to the core lowering the mem to 900-905mhz) Does it worth?? Or is better to keep the previous values?
Thanks :)

jimmor
06-14-04, 05:23 AM
for all practical purposes, it is better to overclock GPU more !!

However since your card has much less adequate heatsinking than a genuine 5950u; running the GPU at 500+ speeds will make it run very hot and therefore likely to be unstable under stress !

So your dilemma is actually more about finding the best GPU and Memory stable speeds for your particular card ? Unless of course you are intending to improve the heatsinking/cooling of your 5900 card ?

also, at extreme overclocks, it is normal that there is an interaction between GPU and memory which affects max speeds !!

rewt
06-14-04, 05:26 AM
Higher core frequency = higher fillrate
Higher mem frequency = higher bandwidth

So your best bet is probably to o/c each as much as possible. However, on games that are highly shader intensive you may actually benefit more with a higher core clock.

SirJpg
06-14-04, 05:46 AM
I am surprised cause the card actually runs very cool ^^ 34-36ºidle and about 59-64ºload( I own a well ventilated Antec case, and there is an 8cm 2500rpm fan pointing directly to the card, wich is cooled like reference 5900s ) However I am thinking of upgrading the cooling system ( by putting "something" on the "naked" side of the card, and buying a new cooler for my cpu that wont exhaust hot-air to the card, like mine´s doing now :( )
So I will keep the gpu as high as posible hehehe as both of u say and cause it was my first idea ( because the lack of shader performance :( )
Now, with 530/910 and it has scored about 6200 with 61.40´s and dx9c with slidebars set to quality ^^

jimmor
06-14-04, 06:05 AM
I am surprised cause the card actually runs very cool ^^ 34-36ºidle and about 59-64ºload( I own a well ventilated Antec case, and there is an 8cm 2500rpm fan pointing directly to the card, wich is cooled like reference 5900s ) ^^

unless your cooling is really good, the 59-64c at load is not real ??

Only way to measure actual GPU temp is to use Rivatuner's realtime Hardware monitor !!

rewt
06-14-04, 06:20 AM
Only way to measure actual GPU temp is to use Rivatuner's realtime Hardware monitor !!

Or SpeedFan 4.12 :) It doesn't seem to lag games like RT does sometimes. Plus you can log CPU/GPU core and ambient temps all on the same graph using different colors. But thats not all!! Show your CPU/GPU temp in the system tray!

jimmor
06-14-04, 06:53 AM
good points to note rewt ! :thumbsup:

I tried SpeedFan 4.12 and like you found it ok. however since i use other monitoring programs for temps/volts/speeds etc, I decided that speedfan was a program too far, and therefore don't generally use it !!

SirJpg
06-14-04, 08:14 AM
unless your cooling is really good, the 59-64c at load is not real ??Well, I read temperatures just after quiting games or benches so maybe I should add at least some degrees?
I use Speedfan for ages hehehe ;) and since I bought this card, another temperature appeard but...that is truly low...and at the same time, another 3 appeard too...
http://www.iespana.es/sirvicente/speed.JPG Here you can see 2 "local" and 2 "remote" temperatures that correspond to 2 sata maxtor hd, the graphicscard and another one that...dunno lol but I cant distinguish them :S
I think the 2 of them that are at the "Max" chip are the hds ( but they are identical, running in a raid 0 config and with a fan cooling them so too much different tª ) and one of the "lm84" could be the 5900?

rewt
06-14-04, 08:41 AM
LM84 seems to be for your chipset. Look under the BUS category, l2CNvidia is for your video card.

SirJpg
06-14-04, 08:47 AM
I have run 3dmark2k3 1 time while Rivatunner was recording ^^
-> http://www.iespana.es/sirvicente/load.JPG

rewt
06-14-04, 08:56 AM
did you let 3dmark run the whole way through? by the looks of your graph it didn't run very long?

SirJpg
06-14-04, 09:10 AM
LM84 seems to be for your chipset. Look under the BUS category, l2CNvidia is for your video card. THANKS!!!! I´ve been looking for an answer like this for a long time :D
So no smart readings form my raid set and final result ->
http://www.iespana.es/sirvicente/speedfan.JPG

SirJpg
06-14-04, 09:45 AM
did you let 3dmark run the whole way through? by the looks of your graph it didn't run very long?
Yes, but I only ran the "game tests" since the rivatunner´s readings were causing awfull performance :)

rewt
06-14-04, 09:53 AM
I see. Keep in mind that temps will increase quite a bit when using features such as AA/AF. At 16x AA / 8x AF super high quality settings mine gets to near 90c after long periods of gaming !! All this at 475/950 stock 5950u speeds.

SirJpg
06-14-04, 10:04 AM
Ok, thanks, I will take care of it :) By the way, did you flash your card? After flashing it my temps went down a lot!

rewt
06-14-04, 10:14 AM
yes. currently running the BFG 5950u BIOS on my BFG 5900nu. I've noticed much lower temps too. I once volt modded my original bios but it was getting so hot it started throttling, locking up, and giving me errors. Not only that, but the card smelled like it was burning LOL so I quickly flashed the 5950u BIOS. No problems ever since :)

SirJpg
06-14-04, 10:28 AM
The same here :D before flashing to 5950 I volt modded the bios and latency but after that... :D