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cwailes

macrumors newbie
Original poster
Jan 23, 2011
16
0
Does anyone have a hi-resolution photo of a Mac Pro Dual 2.66 Logic board? My computer has gone down and I have taken it to an apple store and they have narrowed it down to either the logic board or processors. They don't have the parts in stock so they would have to order them. I want to look at a hi-resolution photo of a good logic board (can't fine one on-line) so that I can zoom into different areas and see if mine looks the same. I have one capacitor that looks iffy but not sure, so I want to compare it to a good logic board.
 
I doubt doing a visual search of a logic board will yield a possible problem. Some things that look iffy can still be good (and yield you a false positive), and some things that could be bad are invisible.

Curious as to why you need to do this... Are you on the hook for parts that don't fix the problem?
 
I doubt doing a visual search of a logic board will yield a possible problem. Some things that look iffy can still be good (and yield you a false positive), and some things that could be bad are invisible.

Curious as to why you need to do this... Are you on the hook for parts that don't fix the problem?

If it's just a busted capacitor, that's an easy fix, which is probably why he wants to have a look.
 
What has happened is that about two weeks ago, my screen saver was frozen. I powered down the mac pro from the power button and then restarted the machine. It failed to boot completely up. It got through the apple logo and then went to a gray screen. I did this about 15 times. I have done everything that I know how and could not get it to boot. I have always been able to fix my own computers, but this was a first. I broke down and took it to an apple store. They ended up having to trouble shoot it part by part and have narrowed it down to the logic board or one of the processors. Me, wanting to try to figure it out myself, took it apart enough so I could see the entire board. I found one capacitor that I questioned. It is a "solid-cap" capacitor that is behind the memory bays. All of the "solid-cap" capacitors that are around it are smooth, but this one in particular is not and has a "K" bulge coming from the inside. That lead me to believe that it has gone bad. However, I want to get a look at a good logic board to see if that particular capacitor is the same.
 
ok, so I received some advice from another forum that suggested I try to boot my Mac Pro with just one of the processors. I tried each processor separately but the machine would not chime or boot. Does that mean that my logic board is bad or does that mean my Mac Pro does not support running on one processor?
 
I'm not quite certain about the 2006 model, but I know the 2008 models will boot with one CPU installed. I would imagine the same would apply here.

It sounds like the Apple tech at the store doesn't have a working 5150 CPU sitting around at his test bench to confirm either way. Therefore, he's telling you it's "either the CPU(s) or the logic board".

But - it's fairly uncommon for CPUs to go bad under normal circumstances, unless they overheat - and the chances of that happening to non-overclocked CPUs with proper cooling are pretty slim. It's likely a bad logic board. Those are a lot more prone to failure than CPUs are. If you do end up going the route of replacing it, make sure the seller has a return policy just in case.
 
I was planning on getting the logic board through Apple. They want $419 for it which is cheaper than anything I have found on-line.
 
I'm not quite certain about the 2006 model, but I know the 2008 models will boot with one CPU installed. I would imagine the same would apply here.

Yes, 2006 boots and works normally with one CPU. Leo Bodnar and other MR member (tobyg if I recall) confirmed that. https://forums.macrumors.com/posts/8965607/

OP, did you check DIAG LEDs on logic board? It's "must-do" thing in such a case. If you're getting "CPU A (or B)" error LED, check graphics card first (or other PCIe cards if you have any installed). I know about at least 2 MR members with "dead logic board, dead CPU" diagnose and in both cases graphics card was a culprit.

Could you post a photo with location of this capacitor? Maybe I can look at mine logic board (I have 2006 too), if it's possible without whole unit disassembling.
 
What I did is switch out each of the processors only in CPU A slot, because I figured it would not work in the secondary position "B." I also kept both heat sinks connected. No I did not look for any error LED lights. I have never really worked on a Mac at the logic board level. I have on PC's but not Mac. I assume the error LED lights are near the CPU's? What color would they be (red)? Also, the only PCI card I have is the Graphics Card. However, Apple checked it and said it was fine.

As for the "Solid Cap" in question, I have attached a photo of the one in question. It is located just above the top memory bay but to the top right corner of that memory bay area on the logic board. You can see that it has the "K" score marks coming from inside the "solid cap." However, if you look at all the other solid caps around it, all of them are smooth, that one isn't.
 

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Check your PM :)

I'll take a look on my logic board and will post picture of this cap if possible.
It looks to me like regular SMD capacitor so if all "rescue methods" will fail, you can try to replace it before you order new logic board. Most of electronics workshops should be able to do it.

Update:

HiRes pics: http://img14.imageshack.us/g/18853293.jpg/

I'm not sure if it's right one (it is in area you've described but your has different specs printed on it). IMO "K" looks exactly the same as on yours. Those caps are just looking like this, I think. "K" has a little "emboss".
 
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Yep, looks the same. I think the cap is fine. It is probably something else on the LB. I will go through all of the trouble-shooting in the SM and see if I can't narrow it down. I really appreciate all of your help.
 
666Sheep,

Ok, I have done the DIAG_LED test and I am able to get the computer to boot off of one CPU and now both CPU's. However, it will only boot up off of my XP professional drive. The only way I can get it to boot is if I move the Graphics card to slot 2,3, or 4. The graphics are all messed up with wide red lines going through them though. It will not boot up on the Snow Leopard drive though with the graphics card in slots 1,2,3 or 4. If I move the graphics card back to its original factory position it will not boot into Windows XP. So am I safe to say that it is the logic board since the machine will not boot with the graphics card in position #1? Or does that mean the graphics card is bad?
 
I just had my Mac Pro (early 2008 8-core 2.8GHz) in to the local Apple dealer, because I had a similar problem. Kernel panic (machine locked up) so i rebooted, and sometimes the screen wouldn't come on, sometimes it would give me a grey screen, sometimes the white apple boot screen. One time it even booted up... But once I turned it off to see if it would boot twice, it went back to the first few problems.

Anyways, long story short, the one time it did boot up, I looked at the crash log, and found that the Nvidia drivers were near the top of the log, so I started googling it, and after taking in for service (under AppleCare for 3 more months still thankfully) it turned out that my NVidia 8800GT was fried. Your problems sound eerily similar to mine, so you might want to try a different video card quickly and see if that resolves your problem.
 
Wow. What beats me is that I took mine into the apple store and they couldn't even get it to boot off of the XP drive. So does that mean they didn't even test the graphics card in different positions? So back to my problem. Can a graphics card cause a machine not to boot if it is fried and in position #1? I don't have another graphics card so I will just have to purchase one try it, if it works great, if not return it.
 
It sounds like your card has died. I had a similar problem with my 7300GT; if you get a boot screen, try holding shift and booting into safe mode.
 
Can I purchase any PCI-Express Graphics Card and it will work with my Mac Pro?
 
Congrats. You saved $419 :D Another Apple techs bad diagnose (or laziness, who knows...) Your card is dead.

In matter of new card: PC one will work only in Windows unless it will be flashed with Mac ROM. Easiest to flash would be ATI 4870 reference card. See flashing threads on MR.

All Apple ATI cards are compatible with your MP, even newest ones (5770, 5870). You can buy one of these.

Apple Nvidia card must be EFI 32 compatible - these which will work aren't worth to bother IMO (except Quadro FX4500 maybe).

If you still aren't sure and you don't want to spend much $$$ for a card to test, buy Mac 7300GT or ATI 2600XT, it would be cheapest solution. You can later replace it with more powerful one.

To finally rule out SLOT 1 failure, you can put there any PCIe graphics card, boot into Windows, install drivers and perform some heavy load tests, like 3DMark or something. If you have one around or you're able to borrow it from a friend, it would be quickest and costless.
 
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Could I not just buy a ATI 5570 or 5870 (from Best Buy) and then flash the memory? Or do I absolutely have to find one that is for the Mac?
 
Yes, you can. But flashed 5770/5870 have one downside: no EFI boot screen via DVI (some have it via VGA adapter). Visit forum.netkas.org for further details, it's the best place to learn about flashing of these cards.
 
So if you had to pick a good card to upgrade to that is easy to flash, which one would you do? I currently have the 7300GT with only 256 of memory. I would like to go to something that has 1GB.

What about this one that is already for mac? Is this too much to pay and I have seen some sites that say that this works with a Mid 2010 Mac Pro. Does that mean it won't work with my Mac Pro?

http://www.cdw.com/shop/products/default.aspx?edc=2184178
 
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It's compatible with all MPs. You can buy it directly from Apple for $249 with free shipping. If you want brand new one with warranty and no VGA adapter fiddling it's good choice IMO.
 
Apple's website says:

Compatibility:

* Requires Mac Pro (Mid 2010) with PCI Express 2.0 slot

Mine is a 1st generation Dual Intel Mac Pro (2006).
 
I believe the 8800GT is about the same, it's only a 512MB card but I've been very happy with mine (other than the failure, but I use my machine for gaming via BootCamp a lot). I've seen em for 200-250.

Oh, and as for your question, yes the fried video card was preventing my Mac Pro from booting. The Apple dealer's diagnosis included some type of check on the on-board (on the card) LED, but I didn't ask him for details.
 
Apple's website says:

Compatibility:

* Requires Mac Pro (Mid 2010) with PCI Express 2.0 slot

Mine is a 1st generation Dual Intel Mac Pro (2006).


Let's call it "marketing BS" ;) It's proven to work with all models - you can read about it almost everywhere except Apple's website.


I believe the 8800GT is about the same, it's only a 512MB card but I've been very happy with mine (other than the failure, but I use my machine for gaming via BootCamp a lot). I've seen em for 200-250.

I'd not recommend 8800 due to its high failure rate.
 
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