Problems ever since installing new memory and GPU

So I originally had an older GPU (forgot the model, but it was NVIDIA) everything worked fine. After installing it, my PC starts most of the time, however, sometimes it will just sit there with a blinking underscore. I have a Samsung 250GB SSD, as well as a HDD.

I keep wondering if it may be because of my PowerSupply (its a ThermalTake Tr2 500w). What information should I supply?

The overall problem: when I boot my PC it sits at the Asus (press f8 to enter bios..etc) however, before I installed my new GPU and new Memory it was never giving me these problems. I've had so many weird problems since this installation. At first, the computer would power on, then power off and then back on again before it loaded windows, now that doesn't happen and now my PC just sits at the BIOS for a long time before loading into windows. Othertimes (only happened about 3 times now) it will load up to windows and show a blinking _ underscore and it will do nothing but sit there with that underscore.

Anyone know anything about this? Am I posting in the right section?

Sounds like you may have a bad piece of hardware. Take the new memory out (is this 2 sticks?) and see if the problem persist. If so it is a problem with the video. If that is not the problem try putting a stick of memory at a time in the PC and see if the problem reappears. You can also run Memtest86 to test the memory.

wyldman68 said:

Sounds like you may have a bad piece of hardware. Take the new memory out (is this 2 sticks?) and see if the problem persist. If so it is a problem with the video. If that is not the problem try putting a stick of memory at a time in the PC and see if the problem reappears. You can also run Memtest86 to test the memory.

I mean after a few times I'm able to boot up fine. It's weird.

That could still mean you have a bad piece of hardware. I have had memory that would work and only error once in a great while. Memtest86 found the problem after a few passes.

wyldman68 said:

That could still mean you have a bad piece of hardware. I have had memory that would work and only error once in a great while. Memtest86 found the problem after a few passes.

Why not just use the built in memory scanner?

I have used Memtest86 for many, many years and it has never failed me.

It works fine now after doing one pass (no errors) and the only thing I changed was I unplugged my 3rd HDD and unplugged my DvD player. Could it have just been that the power supply isn't strong enough to power everything since I got my new GPU? The card said it needs 400w minimum and my PSU is 500w. I thought it would work fine. Any other ideas?