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Turning A FX5900 Into A FX5950 Ultra, Tool-Free
A reader writes "Some very interesting details coming from various tech sites such as ExplosiveLabs and 3DChips that shows it is possible to turn a GeForce FX5900 into a FX5950 Ultra (which is NVIDIA's top of the line video card chipset currently available) through simply using the FX5950 Ultra BIOS on the FX5900 video card."
Basically, if you do this, don't be surprised if your card becomes toast a shortwhile after. Umm, no. If you've ever overclocked, you'd understand that hardware starts getting errors when it's pushed too far. In a video cards' case, it will begin rendering things incorrectly.
The errors start happening LONG before hardware burns up, and is soon as the card is set to a slightly lower speed, the errors disappear.
Basically, if you get your card to where it gives no errors, and are able to keep it around the same temperature, it won't have any troubles.
hey!
Exactly. On the AthlonXP there are jumpers that change the XP into a MP. There is another set that changes it to a Mobile Athlon. More jumpers change a 2500+ to a 3000+ (multipliers), etc, etc. Producting 10 different cores would make the processors cost about $1000 a piece. Selling 3200+s for more than they cost and 2500+s for less make AMD profitable (well, not really. but it's the right idea :)
Anyway, your 2500+ is only guarenteed to run at 1700MHz (or whatever). If it runs at 2200MHz, great. If not, tough shit. If you buy a 3200+, though, then it had better run at 2200MHz (200x11, right?). If not, then you can complain.
Selling underclocked 3200+s as 2500+s allows AMD to sell bad 3200+s instead of throwing them away. The reason that some overclock well is because AMD tests a few out of one batch, and if any are bad AMD brands them _ALL_ as 2500+s. So it's highly likely that you really have a 3200+, but, again, don't count on it.
My other car is first.
Before we get into the hack itself, we need to look at the chips and BIOSes involved. The 5900 cards use the NV35 chipset, and the 5950 uses the NV38 chipset. The two chips are very similar, but they are not exactly the same. This is not the Radeon 9500 to 9700 hack. In that situation, you had an R300 in both cards--here, you have to very similar chips. The differences between the NV35 and the NV38 are slight, at best, and as far as anyone knows, they have more to do with the cost of manufacturing than anything else (I've heard that 5900 cards are so cheap now simply because they are being dumped in lieux of 5950s).
So, where does that leave us? The BIOS hack. Essentially, it does three things to the best of anyone's knowledge:
So, the decrease in performance at the same clock speeds is due to the relaxed memory timings, but just like with anything else, you can get a higher overclock as a result.
HOWEVER--there is one potentially serious problem. Most people have reported that the 5950 BIOS flash has caused no change in the reported temperatures. Given what we know about the new BIOS and increased voltage, this makes no sense. I am, then, forced to wonder if the temperature diode becomes less accurate after the BIOS is flashed with the 5950 BIOS. No one has confirmed this, and since I don't have a 5900 to try it on, I can't either. However, it's something to keep in mind.
Finally, this is not newsworthy in the least. It's the same as people changing 9800 non-Pro BIOSes to those of 9800 Pros and getting better memory overclocks. It's nothing special or magical; you're not doubling the number of pipelines and the memory bus like you were with the 9500 to 9700 hack. However, it works (or seems to, at least), and it's pretty cool.
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