Laptop just started running games slow.

[The Kringle]

Hi, i have a lenovo y580. Its been great until recently when i play games im getting terrible frames.
even in games that dont have high requirements on the lowest settings. i can only think of three things my antivirus expired but i barely go on websites other than google, youtube ect. and that a before this started happening the computer wasnt properly turned off, i think my brother removed the battery while it was on. the last thing is that im almost out of memory maybe a gig left.
thanks for any and all help

CPU/Chipset
3rd Generation Intel® Core™ i7-3630QM (2.40GHz 6MB Cache)
Operating System
Windows 8 64
Memory
6GB (DDR3)
Graphics
NVIDIA® GeForce® GTX660M 2GB with DirectX® 11
Dimensions
15.2" x 10.0" x 1.4"
Camera
1.0MP HD webcam
Display
15.6" LED backlit HD display (1366x768)
Weight
6.2 lb
I/O Ports
2 USB 3.0 ports
2 USB 2.0 ports
6-in-1 card reader (SD, SD-Pro, MMD, MS, MS-Pro, XD)
Headphone jack
Mic jack
S/PDIF
1 VGA port
1 HDMI port
2 mini PCle
RJ-45
Storage
HDD: 750GB (5,400 rpm)
Wireless Connectivity
Intel Centrino Wireless-N 2200BGN
10/100/1000M Ethernet LAN
Bluetooth® 4.0

also notice its blowing out hotter air than normal out of the fan

 

[Danbuscus25]

hmmm well, if you noticed its gotten hotter, replace the thermal compound, and make sure your laptop is well ventilated. also make sure its not on power saver mode

 

[tiler20098]

1. re paste your laptop if you don't know how take it to a professional
2. Make sure your not using your integrated graphics (intel hd)
3. allow air circulation
4. clean your laptop's hard drive and use an external hard drive to save your games and stuff
5. clean your registry
6. make sure you have no viruses (slows down performance a bit)
and good luck

 

[LummusMaximus]

If you only have a gig left, that's likely to be your issue as this will slow the hard drive right down to a crawl, making the entire system feel so much slower. You could buy a 1.5TB laptop HDD, and this additional space may fix your problem. If it doesn't, that's another 750GB you have at your disposal! Maybe it is a virus, you should run regular scans to check. If none of these help, check if it's under warranty. Lenovo are required to help you if it is, so it's always good to check.