Ok folks listen to me. Changing the VID DOES alter voltage, not just a label. This is a myth, and if you would like to try it out please do so. I am currently running the GTX BIOS, with unoptimized memory latencies and the 3D VID has been set to 1.05V. My clockspeeds are currently still at 600/800. I have tried a whole LOT of differing voltages myself, and 1.05V is about as low as I can go while maintaining a high degree of stability at 600Mhz. I have noticed that if I try to run at 1.00V while at 600Mhz, the system will crash within 3 seconds of loading ATITool. At 1.03V, the system crashes after about 4 minutes of ATITool. 1.05V is rock stable, even while running ATITool all night long. At 1.05V, while running with just the 3D window open (not scanning for artifacts), my temperatures peak out at 83C. At a voltage of 1.15V, my temperatures max out at 88C. While running at the stock GTX voltage of 1.24V, I have hit as high as 94C... Tell me again that changing the voltage in Nibitor does nothing...
The fact is that the STOCK GTX memory latencies are already at their optimum settings. I installed a STOCK ROM for the GTX and lo and behold, the memory timings are the same as Juan's 'optimized' rom. The GS is the only video card here that will benefit from this modded rom (as far as memory is concerned anyway... everyone will benefit from the unlocking of the BIOS) If you don't believe me, try it for yourselves. The difference between his 'modded' GS rom and the GSX mod that Yolda originally pointed out is completely superficial. The GSX mod already installed GTX timings onto a 7900GS. However with the GSX settings your NV Control Panel reported that you now had a GTX (even though it still correctly reports 256MB of RAM) Juan has simply modded the original GS BIOS with the GTX timings so that your computer thinks you still have a GS in it. Once again, this is more a superficial mod than anything. This is exactly why you guys are not seeing a benefit from flashing to his modded GS rom from your GSX rom you have been using. ITS EXACTLY THE SAME! Once again, if you don't believe what I am saying try it yourself!
Juan deserves a round of applause for bit-modding the BIOS lock for us. This has been a major inconvenience for everyone, especially you guys looking to hit that 'sweet spot'. However, the memory optimization mod is really just a reverse engineered GSX mod and will only benefit those who absolutely hate seeing the control panel tell them they have a GTX. I have nothing against Juan for his findings, as he did put a degree of work into getting this all figured out. He answered the burning question we all had about "why does the GTX BIOS let us hit 800Mhz plus memory clocks?" Now we can clearly see that the latency was the issue all along.
To say that Dell does this just to make money... well I think that is only half of the equation. The 7900GS uses tighter memory timings than the GTX. By tighter, I mean that the memory physically works faster per clock cycle. The concept is the same as with DDR2 RAM used for regular system memory. If you buy a memory module that is PC4300 for example, you may see that it has more than one timing set that it works with. If you run that RAM at 533Mhz, the SPD would perhaps set the timings to 4-4-4-12. Now if you use that same memory module in a system where the RAM would only run at 400Mhz, the SPD would instead use timings of 3-3-3-9. The latency values are able to be lower (better) at a lower clockspeed. However if you try to run the 3-3-3-9 latencies while also running at 533Mhz, you more than likely will get memory errors and/or freezes in Windows, or the system might just not boot. Of course you may get lucky and have a decent stick of RAM that was underrated at the factory and it may be perfectly stable... The same is true with GDDR3 in a video card. As the latency values get smaller, the potential to run the memory at a higher frequency decreases. You would have to slow the memory down by increasing the timings to allow a significant clockspeed increase. I remember there were many people who used the GSX mod and found very little real world performance increase from it. This is simply because the faster latencies of the GS BIOS outweighed the benefits of the major clockspeed boost and slower timings of the GTX BIOS. Example - GS clocked at 600Mhz memory could/would be comparitive to the GTX memory clocked at 700Mhz.
Dell wants you to buy the GTX because of the higher clockspeeds and more memory. Do they want to make money off of the consumer? Of course they do. The two offerings are there for the sole purpose of variety. Dell probably did lock the BIOS so that we wouldn't have an easy time figuring all of this out. You can be sure that they expected this to happen eventually though... With that in mind, I have a hard time believing Dell did this simply to rake the consumer over the coals. The E1705/9400 and the M1710 are nearing their respective EOL (end of life) periods. Soon Dell will release something bigger and better, and the process will start all over again. They have made their money on this lineup, and what we do with these systems now is in our hands.
In closing, I still will commend Juan for his efforts here. He has done what nobody else here has managed to figure out. I do hope he decides to hang around for a while and hack with the rest of us. Thanks bro, we appreciate the work you have done.