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View Full Version : XFX GTX XXX or simply OC your GTX?


HeavyH20
01-14-07, 12:29 PM
I was curious if a factory OC'd card had any advantages over the stock clocked card that was simply OC'd to the same clocks.

So, I flashed my cards with the XFX XXX GTX BIOS to run some tests. The clocks for this BIOS, stock, are 630 core, 1350 stream and 1000 memory. I tested it with a 3.2 GHz QX6700 with all driver settings at stock in 3DMark06.

XFX XXX - 14,888
GTX OC - 15,232

I think the slightly lower results are due to the 1350 stream clock which is the same as the stock card.

I also suspect the EVGA Superclock to perform a little better since they have also raised the stream clock to 1458 along with the core and memory. So, it seems that XFX, as before with the 7900 GTX XXX which removed the delta to improve the advertised clock, has done something similar with the 8800 GTX.

jAkUp
01-14-07, 12:39 PM
Well, try this..

Overclock your card to 626MHz and check the core/ROP clock with rivatuner monitoring tool. Now overclock to 630MHz and check the core/ROP clock.

Now flash the EVGA ACS3 BIOS and check your core/ROP clock with Rivatuner monitoring tool. Try 630MHz, and check the core/ROP clock.

:)

HeavyH20
01-14-07, 12:44 PM
Yep, already did. The XFX runs the stream (shader domain) at 1350 while an simple OC on the stock card bumps it to 1458, which is coincidentally the same as the EVGA ACS3 or SuperClock setting.

jAkUp
01-14-07, 12:49 PM
I am not talking about the shader clock, I am talking about the core/ROP clock.

HeavyH20
01-14-07, 12:56 PM
Interesting. But, right now, I do not have the ACS3 BIOS. Still looking for that. The only one I have is the first rev from November (non-OC version).

Shocky
01-14-07, 03:55 PM
The factory overclocked cards are slower at the same clockspeeds due to lower shader clock and loose memory timings.. You would have to clock them higher to match or better performance so 8800GTX overclocked > XFX 8800 XXX..

Unless you use extreme cooling where the lower shader clock and loose timings will help you clock higher, would be intersting to know at what point exactly the XXX will beat a standard GTX clocked at 675/2000.

HeavyH20
01-14-07, 04:56 PM
I think the memory timings are the same, but what Jakup is talking about is the actual core clock/ROP value when the clock is set to 630 is actually 621 in this case. But, if you user Rivatuner to OC, the 630 is actually set, it seems.

EDIT: Rivatuner works the same.

jAkUp
01-14-07, 05:01 PM
Actually, it should set 621MHz no matter what you clock it to. If you set 635MHz, you will get 648MHz.

HeavyH20
01-14-07, 07:25 PM
Yes, the infamous delta. The clock you set is mearly determines the clock all everything is calculated from.

jAkUp
01-14-07, 07:35 PM
Yes, the infamous delta. The clock you set is mearly determines the clock all everything is calculated from.

Yup, however, on the EVGA BIOS, it actually is a 626MHz clockrate, 630MHz, is actually 630MHz clockrate.

HeavyH20
01-14-07, 07:55 PM
For the ACS3 version only, right?

jAkUp
01-14-07, 07:55 PM
Yea, ACS3 only.