no prob....

for further info plz reger to the amd vs intel thread.

Expert here, i got few questions:
Is it really worth it to buy sli mobo? Dual gfx card can give 2x speed?
Is dual 6800GT faster than single 7800GT?
6800gt x2 = RM1400X2 = RM2800 = much much much more expensive than 7800GT

If you are a gamer, SLI is highly recommended.

AFAIK, it dosen't provide you double speed. Its just like a dual CPU, it dosen't provide you double speed, but it can take stress.

YOu can actually get the SLI mobo and run a single card first, then if not enough, you buy another IDENTICAL gfx and put it in. Don't lost the SLI bridge.

i duno wher to put this but... i'm been wondering

high end graphics cards we can see alot of silver caps (tantalum capacitors?) on the VGA card itself.. esp at the power regulator portion of the vga card

but in X1800XT series.. there is NONE!!! (except 2 small ones at the fan header ther, perhaps to buffer the fan feedback noise?) at the power regulation portion of the card...how izzit posibble? i tot caps is a must for power regulations together with mosfets + some IC + wayar lilit on a metal ring(inductor?)

if power regulators can be done without caps... imagine motherboards without bulky bendable capacitors

This post has been edited by jinaun: Nov 8 2005, 03:18 PM

Caps don't always look like those cylindrical things that stick out of the card.

ok.. got it..

and.. may i ask, wher is the usual silver cylindrical thing is common on VGA cards... gone to now? replaced by the smaller rectangular yellowish/brownie thing?



This post has been edited by jinaun: Nov 9 2005, 12:32 AM

Attached thumbnail(s)

Yes, they're probably using tantalum capacitors like the prodigy LT

The caps in silver casings are aluminium SMD electrolytic caps. Tantalum chip capacitors come in black, rectangular packages. The regular brown coloured chip capacitors are ceramic caps, they aren't used in power filtering because they have poor effective series resistance (ESR) properties.

Also conspicuously missing in that shot of the X1800 board are the inductor coils/beads used for DC-DC conversion. Hmm...

Thanks for the info
I can see a single coil in the bottom left corner, is that what you are looking for?

oh yeah. heh, I should have paid more attention. I've been mucking about with motherboards recently and gotten used to the multiphase dc-dc topologies so I was looking for more than one.

I'm really curious to know what's under that red strip of heatsink though, Beyond3d had a pic of the board stripped of all the heatsinks, but it was pretty low res and had bad lighting.

MOSFETS?

http://homepages.which.net/~paul.hills/Spe...ol/Mosfets.html

This post has been edited by jinaun: Nov 15 2005, 10:15 PM

so in essence... if 16 phase the ripple thing is 2 amps? how significant is this ripple amp thing.. cos as far as i know a well designed 2 phase is simply better than a badly designed 3 phase

anyone?

Source : http://www.legionhardware.com/document.php?id=476&p=2

This post has been edited by jinaun: Nov 15 2005, 12:22 AM

yah, it's always correct. We don't know if the Asus 8 phase is really that good compare to other 4 phase power. However, from anandtech's review, it seems pretty good..



Anyway, something I found for those who would like to know about the voltage rail purposes of PSU :

Power supplies today rely mostly on the 12V rail for the high current demands of components like the CPU, video card(s), and hard drives (to name a few), with 3.3V coming in a close second for components like memory and PCI cards. The 5V rail has slowly been de-emphasized in favor of the other two rails, however it is still used by a fair number of components (like USB and some onboard chips).

Older power supplies that were designed around the v1.3 specs have a different looking cross regulation graph because PCs from those days relied a lot more the 5V rail for primary power and 12V was not used nearly as much.

source

The ripple amp is there as a side-effect of using a switching mode DC-DC convertor to change the 12V rail into the 1.x volt Vcore. Because Vin/Vout at the convertor is ~10x, that means that the MOSFET is "off" much longer than it is "on". The inductor is charged rapidly while the MOSFET is on, and releases its energy as current during the off stage. This gives us the huge peak to peak current difference that you know as "ripple".

Ripple current is usually filtered off by the decoupling capacitors at the supply pins of the CPU, these are the clusters of multi-layered ceramic (MLC) capacitors you see inside of the socket and on the underside of the motherboard. Higher ripple amplitude means that you need to use higher value capacitors.

Having multiple phases means that as one phase is discharging its inductor, another phase will be charging its own inductor and picking up the current again. What you will get is a sawtooth current waveform that is twice the frequency of each phase. The ripple reduction is not exactly 1/n (n is the number of phases), it depends on what level the "off" inductor's discharge current and the "on" inductor's charging slope intercepts each other.

There are several nice things about having many phases in a CPU power supply line. First off, because each phase has to supply less current, the MOSFETs won't be passing that much current and run cooler. Next, because ripple frequency is higher and the amplitude is smaller, then the bypass capacitors at the CPU can be much smaller.

The most obvious con is cost since you're multiplying the number of MOSFETs, inductors and big Farad, low ESR capacitors on the motherboard. Board area is a cost concern for the manufacturers as well. The CPU's power supply demands fluctuates during use and the controler has to respond quickly to sudden changes. Having more phases to control makes the controller element much harder to design.

VERY GOOD TOPIC!!

Hi All,

Please kindly advise me the spec for desktop pc (just the CPU only) and the latest price for this......thanks.

My sister is looking for INTEL pentium (DUAL Core) desktop pc for processing pictures,and others thing the required nice graphic (need a acceptable graphic card for processing pictures).


Thanks......

post it in hardware QnA

This post has been edited by charge-n-go: Nov 23 2005, 09:02 PM

Hi all, I've reading some reviews regarding graphic cards (i.e. from HArdocp, firing squad etc.) May I know why they always use FPS games for benchmarking (i.e. Doom3, HL2, Farcry, UT, BF2).
Does this mean that if the graphic card get a good benhmarking result for these games, then it can play RTS games (DOW, AOE3, BFME etc.) without a hassle?

Appreciate some info on this.

yes. imo it is because RTS games doesnt have that much of action on the screen whereas FPSes will require you to move around alot and there's a lot of action thus requiring the gfx to churn out more frames. Besides that, technological advancement in the graphics sector mostly affect FPS genre. Take a look at Doom3, Quake4 , FEAR, etc compared to RTS games, it definately looks more eye candy/detailed compared to RTS.

And that is why they use mostly FPSes in their benchmark because these kinda games are the ones that will set certain standards on how games should lookk like.

i am curious about the clock speed of every processor

i know the processor speed is determined by the processor multiplier times the system front side bus.

but my question here is, how is the multiplier of the processor be set? is it set internally in the processor die, or set by the capacitor and resistor value on the processor ( like the old version of amd athlon, where the pencil trick work). what is different inside the processor core of a 2.0GHz P4 and a 3.0GHz P4 of the same architecture, same FSB, same socket design?