VOGONS


First post, by Munx

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So some time ago I got myself a boxed Radeon 9800pro from Sapphire. Later I found it was artifacting. I looked through the card several times before, however I somehow missed a couple of broken components and up until now assumed it was bad memory.

Here it is:

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I see two missing components - a capacitor (C1173) and what I am assuming is a diode (D28)

The pcb and core are based off the later 9800xt:

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I am unable to find any relevant info or decent pictures of the card online and so was wondering if anyone here has this model of 9800pro/xt and would be willing to check the markings of these components so I can get a hold of them and hopefully bring this card back to life

My builds!
The FireStarter 2.0 - The wooden K5
The Underdog - The budget K6
The Voodoo powerhouse - The power-hungry K7
The troll PC - The Socket 423 Pentium 4

Reply 1 of 4, by SSTV2

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Judging by the massive ferite chokes and mostfet count, you probably have a R9800XT there. Missing cap should be just a bypass cap between 3.3 and 10uF (any of them in that range would do the job) and diode is probably a dual schottky which is used for bootstrapping. Use a DMM and PWM ICs datasheet to be certain.

Reply 2 of 4, by Munx

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SSTV2 wrote:

Judging by the massive ferite chokes and mostfet count, you probably have a R9800XT there. Missing cap should be just a bypass cap between 3.3 and 10uF (any of them in that range would do the job) and diode is probably a dual schottky which is used for bootstrapping. Use a DMM and PWM ICs datasheet to be certain.

The PCB and core are 9800xt (R360), but it is a 9800pro.

My repair experience consists of looking at the component stats and soldering replacements with those exact stats and I don't even know how to properly use a multi meter...

I looked up some more images and the missing diode looks to be identical to a nearby one that has "WVII 41" written on it. Any idea what that means?
The missing capacitor looks the same as c1159 and c1156. Is there a way to check what kind of capacitors those are?

My builds!
The FireStarter 2.0 - The wooden K5
The Underdog - The budget K6
The Voodoo powerhouse - The power-hungry K7
The troll PC - The Socket 423 Pentium 4

Reply 3 of 4, by SSTV2

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WVII part doesn't exist in sot-23 package, it's probably a WV4 which would be a dual schottky diode. Here's the datasheet to that PWM: http://pdf.datasheetcatalog.com/datasheet2/2/ … dqrwtxr403y.pdf

In pg. 2, D1 and D2 are bootstrap diodes, see if traces either from pin 3 or 25 lead to the broken diode and the existing one, if it does, then you will be sure that those parts should be identical, have fun 😀

About that cap - it's a bulky SMD cap, again, trace it to PWM IC and use datasheet to confirm that it connects to VCC, if it does - you can replace it with any, same sized, bulky smd cap or even leave it unpopulated. No one will be able to tell you its exact value anyway, because you can't measure those in circuit due to other caps being connected in parallel with it, doh!

Reply 4 of 4, by Munx

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SSTV2 wrote:

WVII part doesn't exist in sot-23 package, it's probably a WV4 which would be a dual schottky diode. Here's the datasheet to that PWM: http://pdf.datasheetcatalog.com/datasheet2/2/ … dqrwtxr403y.pdf

In pg. 2, D1 and D2 are bootstrap diodes, see if traces either from pin 3 or 25 lead to the broken diode and the existing one, if it does, then you will be sure that those parts should be identical, have fun 😀

About that cap - it's a bulky SMD cap, again, trace it to PWM IC and use datasheet to confirm that it connects to VCC, if it does - you can replace it with any, same sized, bulky smd cap or even leave it unpopulated. No one will be able to tell you its exact value anyway, because you can't measure those in circuit due to other caps being connected in parallel with it, doh!

Thank you!

The diodes are indeed identical. I havent managed to confirm the missing cap yet, but I'm almost certain it's one of the three 1uF ones.

Guess I'll be ordering new parts this week 😀

My builds!
The FireStarter 2.0 - The wooden K5
The Underdog - The budget K6
The Voodoo powerhouse - The power-hungry K7
The troll PC - The Socket 423 Pentium 4