– By pressing the power button lights up intermittently, the LED on the left of the SHIFT key but the pc does not start;
– Often feels even turn the fan on power;
– The computer does not display anything on the screen and even attaching an external monitor
– In some cases the PC power emanates classics BEEP that highlight problems to the motherboard (in particular the video processor).
What causes the problem?
If you have this type of problem is very likely that the problem is the AMD Radeon graphics processor that makes the whims.
The thing about this pattern is evident when the fan stops to cool properly (due to dirt or malfunction of the fan itself).
The Compaq 615 Need Adi Reflow Reball Or Graphics Processor AMD
In the situation described here smonteremo pc to get to perform a reflow of both the video processor, both the AMD chip set (although it may not have any kind of problem).
We begin with the disassembling all the covers, hard drive, battery, RAM and WiFi Card. Then svitiamo all the screws of the body including the small screw that locks the burner and obviously detach too.
Detach the upper frame comprising the panel. Eye to the flat which is hooked under the keyboard: we must pull together this too!
Detach the WiFi antenna cables and connector of the webcam:
To get to detach the flat of the video we must first remove the speaker.
After removing all the pins, screws and flat compartment under the keyboard, we can open the two shells being very careful that the flat touchpad remains connected under then AVOID TO PULL brutally upper body!
And here we are finally in front of the motherboard. We must of course also remove this. Simple, few screws securing the connector of the DVD and the motherboard itself. Then you have to disconnect the fan cable and play a little to leverage as the motherboard is stuck her going.
We are now working on the other side of the motherboard, svitiamo heatsink covering the CPU and GPU ATI.
And here are the processors on display. The top one, pictured below, is the ATI Radeon almost certainly creates the problem of blackouts. As can be seen, the edges there is the high temperature silicone (which we will necessarily disconnect).
At the bottom there is a processor that is part of the chipset, always a ATI, which is not covered by the heat sink. Well in my case as it does not cost me a lot to do it, I made a reflow also this component.
But I’m pretty sure that in the vast majority of cases that this component has no problem, so if you do not have much time dwell only on the graphics chip.
We start to prepare the motherboard for the rework of the two processors. The first thing to do is clean the whole motherboard from dust, old thermal paste. Then we have to disconnect the battery and any and all components in rubber / plastic can melt and that are present on the bottom of the motherboard (I mean for the bottom part of the mainboard where there are processors on which we are working).
We attack the thermocouple sensor on the bottom of the motherboard at the processor to work and begin to perform preheating up to 150 ° to eliminate the red silicone with an awl.
After eliminating the silicone, we can proceed with the application the special flux along the edges and then push it below with some air jet or syringe. The flux from the gel becomes liquid and must penetrate well on all sides, so you have to insist for a long time.
Hopefully we can also completely BGA desoldering and then redo the ball of tin and resolder using reflow: in this case it is useless to filter the flux beneath the processor if we detach it completely …
In my case, however, the reflow done to perfection is more than enough, the PC back to work without problems, and the repair is durable: in some cases it is rather rare even need to buy a new processor and resolder latter; I hope that this is not your case because often the only processor costs about 50 euro …
We begin the reflow process following the directions in terms of time and temperature recommended by the manufacturer of the processor.
After making the reflow of the graphics processor and chipset, I eliminate the excess flux, I do it all cool, and remount summarily pc with the main elements (ram, display cable and power button) to see if it lights up regularly.
Obviously I apply before the perfection of the new thermal paste on the CPU and GPU.
Result ?? Lights up !!!!
At this point rismonto display again and the motherboard and work on the fan. This fan, before the repair, was leaving but it was very noisy.
Opening it I see that it is badly put. Besides dirt, pinwheel hand known that it is a bit crooked and especially makes resistance during the rotation.
One of the solutions of course is to replace it. But first I want to try cleaning the rotor of the motor and everything inside it, then unmount and completely step before contact spray dry with a cotton bud and then spray a little more grease to lubricate the moving parts.
After cleaning and drying I feel the fan to operate it at a professional power supply, to make sure it spins smoothly: and it suits me, the fan runs very well and does not make much noise.
Result: I avoided replace, saving a lot of money to the customer (a new fan can cost no less than 25 € …).
Remount the whole pc and do some testing ..
And here is our beloved Compaq 615 return to work without problems !!!
In this case you can change the BIOS setting so that the fan is always on when we feed the computer with the power cord: in the early periods of use, we recommend setting the fan in this way, then we can go back to the basic in which the fan is activated and adjusts automatically only when necessary.