yes. because the backlit keyboard of the Y400 is actually a white light filtered by red filters, making the keyboard emit only red lighting.

i believe adding a colour filter can change the colour of the backlit keyboard. just not sure if the keyboard module have the foil layer soldered or screwed.
see this

detachable laptop? that is called a hybrid, a mixture of tablet and notebook. however, with your budget, it is quite difficult to find 1. so far, the closest model to what you are looking for :

Samsung [Ultrabook] ATIV Smart Pro, i5-3317U + Intel HD4000 + 128GB SSD + (1920x1080; touch)@RM3599[884g w/o keyboard], 4GB, stylus, W8; color: black
Microsoft Surface RT, Nvidia Tegra 3 + 64GB SSD + (1366x768; touch)@RM1849[680g]; WRT, 2GB
Acer Iconia W511, Intel Z2760 + Intel GMA + 64GB SSD + (1366x768 IPS; touch)@RM2199[580g], 2GB, 3G, W8, keyboard dock, 1 year
Acer Iconia W700, i3-2375M + Intel HD3000 + 64GB SSD + (1920x1080; touch)@RM1999, 4GB, W8; BT keyboard

not advisable. i dont see the use of 16GB unless you are a hard core multitasker or heavy autocad project user.
programs will run faster but there isnt much changes if compared.

for mSATA and SSD, mSATA is a RAM like module. the speed of a mSATA is around 350MB/200MB in R/W speed. however, a SSD (which is a hard disk like) can run up to 550MB/500MB in R/W.

the another smart ativ has weaker specs, as the 1 i recommended is Pro version.

WRT - Windows RT, windows 8 version that is designed to run on ARM processors, a mobile phone processor.

the acer uses 2nd generation processor, so it will be cheaper.

This post has been edited by raymondtong94: May 17 2013, 11:11 PM

yes, it is different.

but you have to set the mSATA SSD to run in bootable mode in the BIOS, not as a cache storage or it wont show up as a C drive.

and again, yes. in order to boot faster, you have to install OS into your SSD.

EDIT : regarding your last question, thats not multitasking. that is multi tabbing. and RAM doesnt help in multiple tabs.

This post has been edited by raymondtong94: May 18 2013, 08:54 AM

thanks for adding the point. i never update myself on the mSATA, as i take that as not a compulsory part of the laptop.

be noted that vivotab RT uses windows RT, which is an ARM version of windows 8. so, x86 based apps are not runnable on it. and of course, the performance in intel i3 will better than the tegra chip.

for battery life, vivotab RT is better, with 10h when surfing with wifi vs 6h. have to thanks to the nvidia tegra processor which is in the vivotab RT.

yes, it is possible. but not sure if lenovo malaysia do sell the caddy drive.

the lenovo Z400 will be better than G480. but the heat transfer in Z400 will be poorer than G480, as it is quite thin and the GPU is stronger.

Y400 is the best if you are opting for GPU only but you cant omit the i7 option in the Y400 as it comes as standard configuration.

ASUS A55VJ-SX093H, i5-3210M + Nvidia GT635M@RM2499[2.52kg], 4GB, 750GB, W8; color: black
ASUS [Ultrabook] S550CM-XX140H i5-3317U + Nvidia GT635M + 24GB mSATA + 500GB + (1366x768; touch)@RM2499[2.3kg], 4GB, W8
Dell Inspiron 15R, i7-3537U + AMD HD8730M@RM2499[2.32kg], 6GB, 1TB(5400rpm), W8SL
Lenovo Z500, i5-3230M + Nvidia GT740M@RM2299, 4GB, 1TB, W8; 2 years warranty; colors: chocolate

prices are RSP and negotiable.

Sony Vaio SVE14133CV, i3-3210M + Intel HD4000@RM1999[2.4kg], 2GB, 500GB, W8; colors: pink/white, Vaio backpack
Dell Inspiron 14R, i5-3337U + Nvidia GT625M@RM1999[2.3kg], 4GB, 750GB(5400rpm), W8SL, customizable LCD back cover (silver/pink/red/blue)

prices are RSP and negotiable.

ASUS G55VW-S1216H, i7-3630QM +Nvidia GTX660M (2GB) + (1920x1080)@RM3999[3.78kg], 4GB, 1TB(5400rpm), W8
ASUS N56VZ-S4284H, i7-3630QM + Nvidia GT650M + (1920x1080) + Bluray@RM3699[2.7kg][B&O], 4GB, 1TB, W8; color: black
Lenovo Y500, i7-3630QM + Nvidia GT750M(GDDR5) + (1920x1080)@RM2999, 8GB, 1TB, W8, red backlit, swappable ODD, 120w psu, 2 yrs
Illegear RE-15, i5-3210M + Nvidia GTX660M + (1920x1080)@RM3299, 4GB, 500GB(5400rpm), FreeDOS [CPU Options: i5-3210M - i7-3840XM]

there are upcoming lineup series of notebooks with haswell architecture and newer generation graphics chip around June/July. so it is worth the wait if you plan to do so.

guys, your options (can omit if not applicable to your preferred brand and usage) :

ASUS A45VS-VX028H, i7-3630QM + Nvidia GT640M@RM2999[2.4kg], 4GB, 750GB, W8
Lenovo Z400, i5-3230M + Nvidia GT740M@RM2099, 4GB, 1TB, W8; 2 years warranty; colors: chocolate
Lenovo Y400, i7-3630QM + Nvidia GT750M@RM2799, 4GB, 500GB, W8, 120wPSU, swappable ODD, 2 years warranty
HP [Ultrabook] Envy4-1204TX, i5-3337U + AMD HD8750M + 32GB mSATA +500GB(5400rpm)@RM2399[Beats][1.75kg], 2GB, W8
Dell Vostro 5460, i5-3337U + Nvidia GT630M + (32GB mSATA SSD + 500GB(5400rpm))@RM2199[1.54kg], 4GB, W8SL, 3 cell
Dell Inspiron 14R (Special Edition), i7-3612QM + Nvidia GT640M(28nm Kepler)@RM2799[2.38kg], 8GB, 1TB(5400rpm); backlit keyboard optional

Lenovo Y500, i7-3630QM + Nvidia GT750M(GDDR5) + (1920x1080)@RM2999, 8GB, 1TB, W8, red backlit, swappable ODD, 120w psu, 2 yrs
ASUS A55VJ-SX093H, i5-3210M + Nvidia GT635M@RM2499[2.52kg], 4GB, 750GB, W8; color: black

This post has been edited by raymondtong94: May 19 2013, 10:35 AM

Lenovo Ideapad G580, i5-3210M + Nvidia GT630M@RM1699, 2GB, 500GB, freeDOS, 1 yr warranty

the only best option for you. some more, full filled your needs.

Acer Aspire AO756, 1007 + Intel HD@RM1149, 4GB, 500GB, W8
ASUS Eee PC 1225B, E-450 + AMD HD6320M + (1366x768)@RM949[1.45kg], W7S; colors: Red/Silver/Black, 1 year warranty
Lenovo IdeaPad S110, Atom N2800 + Intel GMA3650@RM1099, 2GB, 500GB, W7S; colors: flower/red/blue/white/black
Samsung NP305U1A, E-450 + AMD HD6320M@RM1399, 2GB, 500GB, W7S
Sony Vaio SVE11135CV, AMD E2-2000 + AMD HD7340M@RM1499[1.5kg], 2GB, 320GB(5400rpm), W8; colors: pink/white/black; Sleeve case

prices are RSP and negotiable.

Dell Inspiron 14-3421, i5-3337U + Nvidia GT625M@RM1699[1.99kg], W8, 4GB, 500GB(5400rpm), 6-cell
Lenovo G480, i5-3230M + Nvidia GT635M@RM1899, 4GB, 1TB (5400rpm), W8, 2 yrs warranty

ASUS A55VD-SX471/472/473, i3-3110M + Nvidia GT610M@RM1599[2.52kg], 2GB, 500GB, W8; colors: black/red/white
Dell Inspiron 15, i3-3227U + AMD HD7670M@RM1599[2.25kg], Win8SL, 4GB, 500GB(5400rpm), 4- cell
Lenovo Ideapad G580, i5-3210M + Nvidia GT630M@RM1699, 2GB, 500GB, freeDOS, 1 yr warranty

best that worth your money is the dell inspiron 14.

Acer V5-471G-53334G50, i3-3227U + Intel HD4000 + (1366x768; touch)@RM1899, 4GB, 500GB, W8
Dell Inspiron 14R, i3-3217U + Intel HD4000 + (1366x768;touch)@RM1888[2.33kg], 4GB, 500GB(5400rpm), W8

prices are RSP and negotiable. use the remaining money to extend the warranty.

if you can wait, then wait for it. your options :

Lenovo Z500, i5-3230M + Nvidia GT740M@RM2299[2.2kg], 4GB, 1TB, backlit, W8; 2 years warranty
Dell Inspiron 15R, i7-3537U + AMD HD8730M@RM2499[2.32kg], 6GB, 1TB(5400rpm), W8SL
ASUS A55VJ-SX093H, i5-3210M + Nvidia GT635M@RM2499[2.52kg], 4GB, 750GB, W8; color: black

prices are RSP and negotiable.

Dell Inspiron 14R, i5-3337U + Nvidia GT730M + (1366x768;touch)@RM2299[2.33kg], 4GB, 750GB(5400rpm), W8
HP [Ultrabook] Envy4-1204TX, i5-3337U + AMD HD8750M + 32GB mSATA +500GB(5400rpm)@RM2399[Beats][1.75kg], 2GB, W8
Lenovo Z400, i5-3230M + Nvidia GT740M@RM2099, 4GB, 1TB, W8; 2 years warranty; colors: chocolate
ASUS [Ultrabook]K46CM-WX177H, i5-3317U + Nvidia GT635M@RM2199[2kg], 2GB, 750GB, W8, OD

prices are RSP and negotiable. regarding your current laptop, have you ever serviced it by cleaning the internal parts? if no, then that is the problem.

IMO, acer aspire s3 is ok only. you are referring this, right?

Acer [Ultrabook] Aspire S3-391-33214G52s, i3-3217M + Intel HD3000 + 20GB mSATA + 500GB HDD@RM1899, 4GB, W8

other ultrabook options :

Lenovo [Ultrabook] U310, i5-3317U + Intel HD4000 + 32GB SSD + 320GB(5400rpm) HDD@RM2599, 4GB, W7HP, Free HDMI-VGA converter; color: Grey, 2 years international warranty
Lenovo [Ultrabook]S400, i5-3317U + Intel HD4000 + 24GB mSATA + 500GB(5400rpm)@RM1999[1.8kg], 4GB, W7HB; AMD HD7450M/W8@RM2199
Dell Vostro 5460, i5-3230M +Nvidia GT630M@RM1899[1.54kg], 4GB, 500GB(5400rpm), Ubuntu 12.04, 3 cell; W8SL@RM2099

prices are RSP and negotiable. use the remaining of your budget to extend the warranty to 2/3 years.

im not a Johor resident, so i dont know.
but as stated it is RSP, anything that is more expensive than the price stated is not reasonable.