Wanna update my iphone 3g baseband 06.15.00

[wizzardox]

Hy,
i have iphone 3g on ios 3.1.3 and i wanna update it to ios 4.2.1. My baseband is 06.15.00 is there any way to update it without downgrading baseband? I was watching videos on youtube where i can use redsn0w to downgrade baseband but when i wanna use 3.1.3 firmware i get error on redsn0w ''That IPSW is not supported by this version of redsn0w'' i have redsn0w 0.9.14b2.

 

[willerz2]

Preserve the baseband. Use RedSn0w 0.9.15 beta 3. Download the 4.2.1 IPSW, open RedSn0w, Extras > Custom IPSW, point it to the 4.2.1 IPSW you downloaded. Put your iPhone into pwned DFU mode (also in Extras), then restore using iTunes or RedSn0w by selecting the custom IPSW that you made.

 

[wizzardox]

Hy,
thx for answer but i now thinking about whited00r, my fried have iphone 3g with ios 4.2.1 and its very very laggy :S. So what u recommended to me?

 

[willerz2]

WhiteD00r isn't supported at all here on iPhoneForums. The reason why the iPhone 3G is slow is because the processing speed and capabilities is almost 1/10th of what the 4S and the 5 are capable of.