Graphics Funky and Glitchy on Old Laptop

I have three Laptops, I was given all of them second (or third) hand and don't know if the parts they have are factory or if they were installed later but here it goes:

One is a Dell Inspiron e1505
Two is an ACER Aspire 3680
Three is an MPC T2400

I have one HDD Between them and its an 80GB SATA Satellite, I have five RAM cards; Two 1GB, Two 512MB, and One 512MB of another brand. (Someone told me that matters)

I switch the HDD around whenever I need to do something different, because all the laptops have their pros and cons, MY PROBLEM IS:
In the T2400, when I put in the HDD and boot it up, the BIOS run fine and it even gets into win 7 x86 Pro fine, too, but once win 7 is up and running the graphics stop loading, the screen freezes and it gets glitchy. It can't be the HDD because it's working fine in the Aspire and Inspiron, I try other OS's like Ubuntu 11 and Hirens Mini XP Boot and the DOS Rescue invironment and I get the same glitchy look to the screen, except it runs a little better. (It just times out the screen sometimes and makes the cursor and windows have ghost trails.) Please help me, I don't wanna buy a new laptop.
 
In my experience, glitchy graphics are caused by one of four things. Faulty OS (doubtful), faulty drivers (certainly possible), a metric ton of dust in the vents (possible, but doubtful), or a dying graphics chip (also possible).

Maybe the previous owner overclocked the gpu, or didn't take care of it properly. Or maybe the laptop is just aging and showing it. Components can fail at any given moment even if they're brand new.

I would try a few things. If you haven't done safe-mode, see if that fixes the graphics glitch. If it does, it's likely to be driver related and you would just have to go to the manufacturer's support webpage and download an updated version. If re-installing the driver doesn't work, and it's not dusty, then it's likely to be dying. That spells "n e w l a p t o p" to me.
 
See if you get the same video on an external monitor? If you do, this indicates that it could be a video driver or motherboard graphic chip problem and not the LCD screen itself
 
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