Failed PS3 Reballing. Solder balls not melting 

here is RIP-FELIX's guide that may help you (assumes you have 2 thermocouples for reading temperatures. One attached to the bottom of the board, another to the top): 1) 120C prebake for 2 hours. The board is entirely covered with tinfoil to prevent drafting. 2) Add flux and increase to 150C (as measured from the TC on BTM side of board underneath the RSX). Usually requires the t8280 to be set to 160C of so (with board covered in foil, the difference is usually pretty small). I cut square if foil to cover the masked off RSX, so it isn't cooler than the rest of the foil covered board. Wait 5 mins for temp to rise and flux to activate. 3) Reflow phase: I set the t8280 to 200C hoping to raise the btm board temp to near 180 or 190. The t8280 is doing 90% of the heating. 4) the hot air only has to get it to 218C from there. This is when I turn on the hot air wand with 45x45mm BGA nozzle. I set it to 200C full air to begin with, let it get it to temp, then remove the foil square and position it over the rsx about 1-2cm over it. Anyway, this is where I monitor top/btm TC's closely. I manually back the hot air off if the top is increasing faster than the bottom and if they temps are rising too quickly. I try to maintain a 10C difference between top/btm TC's and 1-2C per second rise, but that's less important than "feeling" whether or not the board is taking to the heat. When temps appear to be plateauing, meaning they aren't rising at the same pace or too slowly, I can tell if there is moisture because the TC's will read 10-20C lower than the setpoint, and usually there will be a larger temp difference between top/btm TC. That's how I know it's time to stop and let the board cool back to 120C for longer. This usually doesn't happen after a 2 hour bake. But almost always does if I bake for less time!. 5) Assuming the board has reached 185-200C and the TC's are close (based on feel), I start raising hot air temps from 200 to 240C. Again I monitor TC's and manually back off and lower the nozzle to mimic the profile. Then from 240 - 270C if the TC's plateau below 235 (the temp I'm looking for based on my cheap TC's inaccuracies. Real temps are close to 20 C lower, so 215 or so). Now I know I'm close. The flux is smoking at this point. If 270C isn't enough to get the top TC to read 240 (the point most of the time LF melts IME), then I start to worry, but not panic. Some chips need more heat than others, but this is where popcorning the VRAM and delam can start happening, so I'm being exta careful to not raise temps too quickly! I don't like waiting at tis temp, most reflow profiles want you to only be at reflow temps for 30s or less, but that's for perfectly dry boards and fresh solder. These are old moist boards with oxidized hard solder. They need more time! So I don't worry about the time (I rely on the hot air to not overheat the hips). IR will keep heating and black chips absorb the heat more. So this is bad advice for IR reballing! But how air heats everything the same! So I can trust my TC's and setpoint aren't hurting the chip as much. Only what's necessary to get the residual moisture out, which could be holding the temps back, and get the solder to melt. Usually I don't need more that 270C, but on some boards I have gone as high as 320C with the hot air (in this controlled fashion), stepping it up as needed based on experience and feel.

i think you need a square nozzle for your hot air to spread the air equally, there are different square nozzle dimensions, and a stand to hold the hot air gun

not an expert, but i did some reballs on a grill with a hot air station, you need much more heat on the hot air and don't aim at the chip like you did, go around the chip all the time. You were measuring around 175ºC on the board, u will need a bit above 220, so you were kinda far from removing the chip there. Flux under the chip also helps to make it faster/easier. My tip for you, get a trash board to practice, do like i said above, when u remove the chip, you clean it and measure all capacitors looking for shorts. If there's no bubbles and no shorts on the chip you will be on the right path.

Your bottom temperature is way too high but hot air temp is not high enough, like someone already pointed out. The nozzle and the stand are missing. Also chances are your ram got damaged on that first lift, so you need to make measurements to the chip before soldering it back. I recommend you join our chat , we'll be happy to teach you .

You must use the BGA REWORK

See my comments in the other video. Good luck 🤞

LE FALTO MAS TEMPERATURA A ESTACION DE AIRE POR ESO NO LO PUDISTE SACAR

Also not an expert... Base is too hot, nozzle too cold like they said. Base at 210⁰c and got air gun to 290 - 300⁰c works for me. DON'T force the chip like that, you will rip some pads! When solder has melted, chip will move a little when touched sideways. It will then be ready to be removed Remember that factory balls are unleaded, which means that melting point is around 275⁰c. When soldering back with leaded balls, hot air gun can be around 280⁰c. I usually let my boards at least 12h on a oven at 60⁰c to remove humidity. Practice on dead boards. A lot. Get yourself a square nozzle and a cheap ass microfone table mount, it will do wonders.