Toshiba satellite A665D-S6082 Ram upgrade issues

Hey everyone, this is my first post on here so i'm hoping i can get some help. I have a Toshiba Satellite A665D-S6082. Specs can be found here Toshiba Satellite® A665D-S6082 16.0" widescreen Laptop (Black) | Laptops | Computers | us.toshiba.com but to shorten it, i have a phenom 2 triple core 2.2ghz processor, an ATI mobility Radeon HD 5650 and 4200 graphics cards, it came with 2 x 2g sticks of so dimm 204 pin pc3-8500S ram, and i recently bought 2 x4gigs of so-dimm ddr3-1066 F3-8500CL7D-8HBSQ from G.skill, and i'm having some trouble making it work.
I first triedputting all 8 gigs in, and it would load up the toshiba screen, and then give me a black screen with the little white underscore mark, and would stay there. i restarted, checked the bios, and it recognizes all 8 gigs. so i took one stick out, put my old 2 gig back in, and it booted up fine. went to properties and it says i have 6 gigs of ram with 4.5g usable. so i shut it off, switched out the 4 gig stick with the other 4 gig to check it also, and it again booted up fine. I've searched online trying to figure out what the problem is, some people say it's a BIOS issue, so i went to the toshiba website and checked, but since my model is discontinued, they dont have a link for it on the website, and i have no idea what else to do. I've tried pretty much everything i can think of, including disabling legacy USB in the bios, because i read that online somewhere too and cleaning the tips of the ram with an eraser and trying them. but i'm lost now, and i'm in the military as an IT specialist. lol. Any help would be very much appreciated. Also, I'm Running Windows 7 64-bit.

 

Have you tried another 8 GB kit? Maybe one of your sticks are bad..

 

From things I have read numerous places in the past, Toshiba laptops can be finicky about which brands of RAM they will accept. Not sure if this is the problem in your case or not.