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I have a laptop, HP EliteBook 8540p having originally 4GB RAM and I've recently bought Corsair Value Select SO-DIMM 16 Go (2x 8 Go) DDR3 1333 MHz.

It fits the required RAM specifications perfectly, and once I've inserted them, the BIOS recognizes the memory correctly, but my linux Gentoo running on kernel 3.1.6 SMP x86_64 crashes immediately when I'm running an app which consumes a lot of memory. The laptop crashes as if there's no more battery left, when the memory reaches at least 6000MB ram.

Windows 7 doesn't want to run anymore, it shows a blue screen with the IRQ LESS OR EQUAL error if I set 8GB, and it doesn't boot at all if I set 16GB.

Is there something I could do to fix this please ?

EDIT: I've ran the latest version of memtest, it freezes within 3 seconds showing weird colors on the screen with a single 8gb ram and both ram plugged. Of course it works perfectly with the original memory devices I had.

Are these memory devices corrupted ?

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Post the specifications of the laptop for us. It sounds like you have at least one bad modual. I also suspect your motherboard does not support more then 8Gb of memory or at the very least at the current speed. – Ramhound Mar 20 '12 at 11:24
I've just done a dmidecode and it says Maximum Capacity: 8 GB That's really weird, the bios tells me there's currently 16GB installed. Well, if I put only 8GB (with one RAM device), linux crashes too when it reaches 6GB ram. My full dmidecode : – Axel Isouard Mar 20 '12 at 11:29

2 Answers 2

up vote 3 down vote accepted

It seems the HP EliteBook 8540p can only support a maximum 8GB of RAM (4GB per slot). This would explain why you're getting the "Maximum Capacity: 8 GB" in your dmidecode.

IRQ LESS OR EQUAL usually suggests a problem with memory also.

Hope that helps!

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I've ran the latest version of memtest, it freezes within 3 seconds showing weird colors on the screen with a single 8gb ram and both ram plugged. Of course it works perfectly with the original memory devices I had. EDIT: Oh, it's 4GB per slot, so it will deny 8GB in a slot then ? – Axel Isouard Mar 20 '12 at 12:32
Four is usually more than eight.. so yes. – ekaj Mar 20 '12 at 12:38
My advice would be to see if you can get your memory kit refunded/store credit and purchase a 2x4GB kit. – sleepyscene Mar 20 '12 at 12:45

first off you need to know what you have there. please. is it a QUAD CORE? 40p and 40w both have i7 quad cores as an option. and the memory needs match or better the speed of your processor. (not stated) back in , 2010 i5 or i7, (520M or 820QM?) (the Q is quad) there are 2 slot mobo and 4 slot main boards. the 2 slot is 8GB max. and 4slot 15GB max. (im running 12,NOW) the memory purchase here are tricky. limited buy i5 or i7 mem, manager, not HP.its and Intel limit. (it connect directly is why) the next limit is the memory must be 1.35v rated. i have 3 of these laptops build from piece parts cheap.... (retired tech)

don't be fooled, i have this old (nice) 2gb Samsung stick that is 1.5v and runs great until it gets warm and fails memtest86, as it slows, from heat. and is just a waste of time, it is the wrong memory here.

the 2GB sticks are easy, and many work, 1.35v or dual voltage sticks. but not the 4gb, and 8gb sticks are not supported at all. HP has no spec page on sticks, so use intels. (HP sells memory only that works)

the only 4GB sticks that work are ones with 16chips called low density. again 1.35v sticks. put them in in pairs on the i7 quad core. on the i5 with 2 SO-dimm slots only 2x 4gb is max. now the topology rules cleary stated in the intel data sheet. (this is all anyone has)

can i have external links, or will you kick me off here like forum-seven did. there are no ads on page, or cash collected.

see that matrix chart here. for 4g. you need 16 chips, 8 front and 8 back if you go to the store like BB, they have high density memory that will not work, with this old processor

but wait , these do. Kingston ACR512x64d3s16c11g Crucial. CT51264BF160B Hynix HMT351S6CFR8A-G7/H9/PB Samsung (see these old sticks 2010)

most modern memory fails here.

it says, not to make statements on opinion. wow. that is rich.! HP has no spec. sorry that is A FACT. and intels is 5 years old. now, almost 6. and they DO NOT REVISE spec's on 5 year old processors to match modern memory leaving what?, OPINIONS and my testing...

this is complex, but not as bad as overheating, that i cured. Getting the right memory is not trivial. cheers and good luck.

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