A separate card reader that plugs into USB would be a good test actually. You can get them for cheap on Amazon, Newegg, and Ebay. [ If you're really thinking about buying another computer, I was going to say you might want to wait for Windows 10, as it will no doubt be an improvement over the confusing interface of Win 8. (The version name of Windows 9 is going to be skipped) But that is reportedly not going to be released until late 2015 . So I'd make sure I was at least getting a free upgrade to Win 10 when it arrives. ]

More than likely you have the "Spiral Balance System" on your windows. If they are failing and not staying up that's the one that fails the most (as Brushworks stated). Usually it's noticed most easily when you lift the sash and it slowly slides back down. These are usually located behind a valance cover which is snapped in the frame or visible in the frame above the lowe sash when closed. If you have a cover in the frame pocket vertically. It may be behind that cover. You have to remove it to see. I wouldn't do this as some of them are a nightmare to put back in place. These fall off sometimes and also just loose some strength as the years go by. Most window installers carry a spiral spring winding tool for adjusting the tension on the springs. It's very easy to do and only takes a couple minutes to do. With your windows only being eight years old I would assume they are still under warranty and can be fixed at no expense to you. Just contact the manufacturer and have them send out the local service tech for repairs. The steel coils or "Constant Force Balance System" is the system most used today. You can see these plain as day when the window is closed. There will be coil covers with a screw in them inside the frame just above the lower sash when closed. These can be some what difficult to adjust. In some minor cases the coil spring comes unwound or disconected from the sash. In this case the sash would feel like nothing is holding it up and slams shut when lifted. This would also still be covered under the manufacturers warranty on an eight year old window. Call them for service. There are still some of the manufacturers who swear by the "Block & Tackle System" like Andesen & Pella. These are real easy to see because all you see is a small cord running up the inside of the frame from top to bottom. If it's loose and hanging, it may have snapped or came disconected from something. The cord is connected to a spring located inside the frame. The cord comes up over a pulley at the top of the unit and then down to the bottom of your sash. You can usually see this cord and reach in and check the tension on the cord. When the window is closed you should have a tight string as if it were a guitar string. There is one on each side of the sash. In most cases you should have a tilt in sash which allows you to look inside your spring assembly. If you tilt your window in to 90 degrees from the frame it can also be removed from the frame. In most cases the sash at 90 degrees will lock the springs sliding connectors in the frame. You can then lift the sash up and out of the frame. The bottom of each sash will have a sash pin which locks in these blocks for easy removal. These pins should have the spring blocks to lock into on both sides. Sometimes people remove the sashes for cleaning and don't get those little pins back in the blocks right. If one side locks in and the other doesn't. You'll only be working off one spring. The other one gets pushed to the bottom and fails to work. Just tilt your sash in and make sure each pin is locked into the springs sliding block. If you see only one side is in place then remove the sash and locate the spring block. It may have snapped all the way up or got stuck at the bottom. You can move the sliding spring block with a large flat screw driver and turn the rotating sash pin lock to lock it in place. Just slide it up or down to match the one on the opposite side. Ounce you get it there you can just quarter turn the inside cam lock to lock it in place with the screw driver. Make sure the pins are tight on the sash and both are in place. Sometimes these pins snap off or break. If ones gone you'll need a new one. If they are both there then put the sash back in and make sure the pins slide into each side and lock in place. Close the sash and push the sash all the way up. Look inside the frame and make sure both springs went up with the sash. If so your good to go. If not you need to do it again until they get locked in. In most cases you should be covered under your manufacturers warranty on an eight year old window. Just have them come out and check them out. Hope this makes sense. Good Luck!!!

You might want to see how the mechanism is attached. Sometimes, you have to remove part of the sill to reach the screws that hold the operator in place. I think that you should also check building codes in your area because windows may be the only point of egress for a room and would have to remain operable. They do make a smaller T-shaped crank that can replace the longer handle, but it still protrudes a bit. Here is a link that might be useful: T-shaped Handle

There are no electronics on this unit. Old-style mechanical thermostat. Sounds like the thermostat is erratic per your description but a proper diagnosis is needed to confirm it. How long are you waiting for the compressor to cycle back on? Could be the sensor (capillary tube) got disturbed recently, positioned wrong and getting a false reading. Some are supposed to be attached to the evaporator, some aren't supposed to touch it. The thermostat is Part Number WJ28X10009. Variously tagged as no longer available and/or out-of-stock. One source says out-of-stock but ships in 5 to 6 days. There's one on eBay claimed to be new-in-box item. You can buy a new 5K BTU unit from Walmart for that price. Genuine GE WJ28X10009 - New As mentioned above, a possible workaround as long as the unit otherwise runs is to rig-in an external thermostat. The device plugs into an outlet, then the unit is plugged into it and is controlled by it. The thermostat on the A/C should be set to the coldest position for the external thermostat to operate it. Lux WIN100 on Amazon Hycency Temperature Controller on Amazon