Help needed diagnosing boot failure

[VVrath]

Heya,

I've been upgrading my computer this weekend - basically, gutting it but keeping my PSU, case, HDDs and DVD Drive.

I've replaced the innards with:

• Gigabyte P35C-DS3 Motherbaord
• Intel Core2Duo E6420 CPU
• 2*1Gb Geil DDR2-6400 4-4-4-12 RAM
• Sapphire X1950XT Graphics Card

As far as I can tell there should be no incompatibilities between the above. Anyway, I've assembled everything carefully (even used my Anti-Static strap!), but the bloomin' thing won't post - doesn't even give a single beep. I've tried:

• Checking and re-seating all cables
• Checking and re-seating all components
• Disconnecting everything except the Mobo, RAM, CPU, Video Card and Heatsink Fan.
• Swapping the Graphics card out for one with lower power requirements (Apparently 580W might not be enough for a 1950XT )
• Removing and re-seating the Mobo.

None of which has made the slightest bit of difference. So basically I'm down to trying to figure out what's broken - CPU, Mobo, Memory, Graphics Card or Power supply.

The PSU is a 580W Hiper model, which worked perfectly with my old Motherboard/Processor/Memory/Graphics Card, so I think I can ignore that.

Changing the graphics card made no difference, so I think I can ignore that too.

Does anyone have any tips on diagnosing which of the remaining parts is dodgy, other than trying each component out in an otherwise known-good PC?

[excalibur2]

Heya,

I've been upgrading my computer this weekend - basically, gutting it but keeping my PSU, case, HDDs and DVD Drive.

I've replaced the innards with:

• Gigabyte P35C-DS3 Motherbaord
• Intel Core2Duo E6420 CPU
• 2*1Gb Geil DDR2-6400 4-4-4-12 RAM
• Sapphire X1950XT Graphics Card

As far as I can tell there should be no incompatibilities between the above. Anyway, I've assembled everything carefully (even used my Anti-Static strap!), but the bloomin' thing won't post - doesn't even give a single beep. I've tried:

• Checking and re-seating all cables
• Checking and re-seating all components
• Disconnecting everything except the Mobo, RAM, CPU, Video Card and Heatsink Fan.
• Swapping the Graphics card out for one with lower power requirements (Apparently 580W might not be enough for a 1950XT )
• Removing and re-seating the Mobo.

None of which has made the slightest bit of difference. So basically I'm down to trying to figure out what's broken - CPU, Mobo, Memory, Graphics Card or Power supply.

The PSU is a 580W Hiper model, which worked perfectly with my old Motherboard/Processor/Memory/Graphics Card, so I think I can ignore that.

Changing the graphics card made no difference, so I think I can ignore that too.

Does anyone have any tips on diagnosing which of the remaining parts is dodgy, other than trying each component out in an otherwise known-good PC?

I had your problem for about 15 mins as I didn't plug the four pin conector into the motherboard.

[VVrath]

I wish my problem was that simple, but I've checked that three times now

I've now tried running the PC with no Graphics card plugged in at all (Same Result), no memory (same result) and just because I couldn't think of anything better to do, no CPU (strangely enough, same result!).

I hate boot problems - its bad enough trying to decipher post beeps, but when you get none at all, it's even more annoying

[excalibur2]

I wish my problem was that simple, but I've checked that three times now

I've now tried running the PC with no Graphics card plugged in at all (Same Result), no memory (same result) and just because I couldn't think of anything better to do, no CPU (strangely enough, same result!).

I hate boot problems - its bad enough trying to decipher post beeps, but when you get none at all, it's even more annoying

Surely the fan works on the PSU when connected to the motherboard?

[VVrath]

Yeah, the PSU fans spin merrily when I press the power button, as does the CPU fan, System fan and Graphics card fan. Something a little weird, though - approx two seconds after I press the power button there is an audible (but slight) increase in fan speeds. Don't know if that's symptomatic of anything...

Looks like I'm going to have to phone round some friends and see who's willing/able to test the CPU/RAM, and if they both check out OK, I guess it's time to RMA the motherboard.

[Splash]

Disconnect all RAM and see if you get a "No RAM" beep

[excalibur2]

Yeah, the PSU fans spin merrily when I press the power button, as does the CPU fan, System fan and Graphics card fan. Something a little weird, though - approx two seconds after I press the power button there is an audible (but slight) increase in fan speeds. Don't know if that's symptomatic of anything...

Looks like I'm going to have to phone round some friends and see who's willing/able to test the CPU/RAM, and if they both check out OK, I guess it's time to RMA the motherboard.

Checked everything outside the computer case?....... pillar shorting the board etc

[BUFF]

try with only 1 DIMM installed.
The default Vdimm may be the JEDEC standard 1.8V & the Geil iirc needs 2.1V to run at it's rated speed.

[VVrath]

Disconnect all RAM and see if you get a "No RAM" beep

Tried that, but still nothing

Checked everything outside the computer case?....... pillar shorting the board etc

Yup - even tried assembling it all outside the case to make sure it wasn't a short-to-earth problem, but it's still sat there not posting.

try with only 1 DIMM installed.
The default Vdimm may be the JEDEC standard 1.8V & the Geil iirc needs 2.1V to run at it's rated speed.

I've tried it with just 1 DIMM in, in every possible configuration (tried each DIMM in each of the 4 DDR2 sockets), but still nothing.

I'm assuming now it shouldn't be the memory that's at fault - surely I'd get some POST beeps complaining at the lack of memory? That's certainly what happens if I remove the RAM from my old Motherboard.

I think I'm going to have to get hold of a known-good CPU and try it in my board, and if it still doesn't work, I'll have to assume it's the motherboard that's at fault and return it.

Thanks for all your suggestions!

[excalibur2]

I've had a situation when the computer wouldn't boot and the hard drive and fans were spinning, turned out to be the PSU.
Anyway let us know what was the answer.

[Mithrandir]

The culprit seems to be the PSU or possibly mobo if other parts have no effects.

[Splash]

If you get no POST beeps with no RAM I would strongly ecommend you look at RMAing the board

[VVrath]

The culprit seems to be the PSU or possibly mobo if other parts have no effects.

That's definitely what I'm thinking - both of those components are more likely to be dead than the CPU. Do you think I can discount it being the PSU as that worked (and still works - I just tested it) with my old motherboard?

If you get no POST beeps with no RAM I would strongly ecommend you look at RMAing the board

But would a functioning board give post beeps if the CPU was faulty? I've just bought a cheap Celeron CPU for the princely sum of £10 on eBay. I'll whack that in and see if it gives the same results. If it is, I'm tempted to RMA the board. I bought it from Scan, and have heard their RMA process is relatively pain-free, I just hope that it (or at least something!) turns out to be faulty rather than just being incompatible.

Diagnosing faults like this is a PITA if you don't have access to a bank of known-good components to swap around and isolate the problem.

[VVrath]

That's definitely what I'm thinking - both of those components are more likely to be dead than the CPU. Do you think I can discount it being the PSU as that worked (and still works - I just tested it) with my old motherboard?

Bad form to reply to your own post, I know, but I just managed to borrow a PSU to test my new components with, and it had absolutely no effect! Still no POST

My temporary replacement CPU should be here tomorrow - if that doesn't work then I will RMA the board and return it this weekend. Anyone know how good Scan are when it comes to dealing with walk-in returns? (As luck would have it I'll be driving through Horwich at the weekend, so though it might be easier/faster than relying on posting it down). Perhaps that question would be better suited to the Scan Care forum nearer the time.

[nutter99]

Wouldnt it be just annoying if the problem was the PC speaker either broken or just incorrectly plugged in?

[VVrath]

Wouldnt it be just annoying if the problem was the PC speaker either broken or just incorrectly plugged in?

I had a brief nightmare about that the other day, but it's definitely not the speaker/speaker cable - for one, there's no display from the graphics card. Also, the speaker/cable work with my old motherbaord. Finally, once it's powered on you have to hold the power button for 5 seconds to power off rather than just press it the once - I'm told that's a pretty clear sign that the Motherboard or CPU has had it.