These have more or less similar specs:
15.6"
Acer
E5-571G-63CGs, i5-4210U + Nvidia 840M@RM1999[2.5kg], 4GB, 1TB, W8.1; colours: red/brown/silver
E5-571G-94MSr, i7-4510U + Nvidia 840M@RM2599[2.5kg], 8GB, 1TB, W8.1; color: red
V3-572PG-94RD, i7-4510U + Nvidia 840M + (1366x768; touch)@RM2899, 8GB, 1TB, W8.1

Asus
K551LN-XX251H, i5-4200U + Nvidia 840M@RM2299, 4GB, 1TB, W8.1
K551LN-XX250H, i7-4500U + Nvidia 840M@RM2899, 4GB, 1TB, W8.1

HP
Pavilion 15-N271TX, i5-4200U + Nvidia 840M + 8GB SSHD + 500GB@RM1999[2.33kg], 4GB, W8.1
Pavilion 15-N227TX, i5-4200U + Nvidia 840M@RM1849[2.33kg], 4GB, 500GB, Ubuntu
Pavilion 15-p036TX, i7-4510U + Nvidia 840M@RM2499[BeatsAudio], 8GB, 1TB, freeDOS; W8.1@RM2699
TP500LN-CJ073H, i5-4210U + Nvidia 840M + 24GB mSATA + 500GB HDD@RM2499, 4GB, W8.1
TP500LN-CJ088H, i7-4510U + Nvidia 840M+ 24GB mSATA + 500GB HDD@RM2799, 4GB, W8.1
Envy Touchsmart 15-J114TX, i7-4200M + Nvidia 840M + (1366X768;touch)@RM2999[2.56kg], 4GB, 1TB+8GB SSHD, W8.1

Lenovo
Z50-70, i5-4210U,Nvidia 840M + (1920x1080)@RM2399, 4GB, 1TB, W8.1, 2 yrs
Flex 2-15, i7-4510U + Nvidia 840M + (1920x1080 IPS; touch)+ 8GB SSGD + 500GB HDD@RM2799[2.3kg], 4GB, W8

MSI
GP60-2PE-026MY, i7-4700HQ + Nvidia GT840M + (1920x1080; anti-glare) @RM3299[Dynaudio], 4GB, 1TB HDD, W8.1
GP60-2PEY, i5-4200H + Nvidia GT840M + (1920x1080; anti-glare) @RM2899[Dynaudio], 4GB, 750GB HDD, W8.1
*Prices in RRP. As you can see here, the Nvidia 840M is actually a very common and entry-level GPU.. so if you are really into gaming, it might be a better idea to save more and opt for a higher end GPU