4GB Ram Upgrade cause Vista fail to boot

I am having a HP Pavilion 6716 laptop. It came with Windows XP. I installed Vista and found it as slow. I contacted HP and asked for ram upgrades. But they were too slow to response. As per system specification I ordered a 2GB stick of RAM. It is a regular DDR2 PC2-5300 RAM. And it is compatible with the laptop. After adding the RAM in the system the system simply failed to boot. There is a bit difference between both the ram models. But I think that can ignored. The old one is 533Mhz and new one is 667Mhz. So does that can cause any kind of problem. Thanks.

It will not boot. Whatever system you have you need common RAM specification. You will need to remove one of them. You can either use the old one or new one. Many motherboard does not supports different Mhz rams. You can contact HP for proper RAM specification and return the one you had purchased recently. Or simply contact the vendor and ask for exact RAM specs that your laptop has.

I am having a 6717 model of HP system. I am having a similar issue where after adding a 4GB RAM I am getting constant blue screen. I had discussed with many for my problem and all of them told me to ship the laptop back to HP for replacement. It took time but now all stuff is working fine. So it is recommended that you buy the original and compatible parts only. Because if buy the same from ath ird party vendor and if that is not compatible then you cannot do anything.

Always before adding a 4GB ensure that what system you have. A 32bit OS or a 64bit OS. This creates a bit issue after purchase. For 64bit system it is quiet enough to go for 4GB or higher ram. While a 32bit system cannot read more than 3.5GB. That is the hardware limit and you cannot do anything in that. Another thing that really matters is the internal specification.