[Galaxy S I9000 General] cbdrift:
I have tried all the gps software fixes and found that they improve things - but dont solve the problem - so i started looking at the hardware from two viewpoints and another software fix from the forums here (ntp time client)

new antenna - can it be retrofitted

electrical noise - can it be insulated out (dont hit reply just yet - you'll see in a sec)

if you open the back cover of the phone - and with the camera facing you from the top left and speaker in top right both facing you - there is a sticker running down the right hand edge of the phone - from the wrist cord holder point to the antenna plug at the bottom of the sim.

from photos on the net of breakdowns of these phones - thats the gps antenna behind there... :)

its a sticker - like the nokia n95 - which has ****ty gps issues that are the same as ours

so i pressed down on the sticker while i was watching the gps signal strength and lo and behold - it changes - a lot.....

the bit of the sticker closest to the sim card where the plastic case between the sticker and the metal part of the sim holder is thinest - i went carefully over the whole area rubbing the sticker firmly down onto the phone guts - result - much improvment for me....

I also noticed that some roms seem better than others.... overclocked roms for me were strange because the gps worked pretty well

...on the undervolted ones

so i tried a kernal with undervolting and setcpu the speed down to 400/400mhz - yeha - it was slower but still faster to me than a sony x10 from the play round on one i had :P - but the gps signal improved for me and so did accuracy

underclocking and undervolting the cpu cut down on electrical noise in the circuts in theory i thought .... hey - easy to try and it works for me....

"this works for me" your mileage may vary

i have agps turned off - using standalone - i have supl set to default even tho it shouldnt be used with agps off - and i optionally use wifi and usually dont use sensor assist

im not saying its perfect

im just saying it improved things for me enough for me to post something about it

when I put the software, supl, agps, standalone, ntp client for atomic time sync to gps times and even at 400mhz - im happy to say its "better" than when i got the phone :)

(wow - confidence inspiring words - but hey - you get what you pay for and this is all free :P)

look at the pic breakdowns of these phones and how the gps antenna is a sticker with two contacts that sit against a component on the phones main board - but if they dont touch right - like the n95 nokia has issues with their stick on antenna - then youll get ****ty gps

i can see an outline under the sticker thing after I was done of some channels it sits over that show up now - but i wouldnt condone trying to make the front and back faces of the phone meet when your pressing things together....

Best thing i like about these things is that they are "free" things to try...

also my black screen coma mode seems to be duplicatable in effect if i fiddle around with setcpu clock speeds - sometimes itll coma out just on the clock speed change....

a govner issue making things play up?

I also saw that there are 3rd party stick on antennas that might be retro fittable to the phones without having to open them up past changing the sticker - but i havnt bought one yet or looked into it past going "wow my gps is going better for me - yay" :)