It is not advisable to list the prices of the things they sell.
From the seller point of view, If they list the product for example like G5 is $1000 (anyhow quote).
a) The distributor/maker may tick off the shop for selling below the recommended sale price and 'blacklist' the shop by passing their stocks to other shops instead.
Harvey Norman don't have this problem cause all their products are at MSRP or the Recommended Retail Price, so can just display the price tag.
b) If you displayed the price at $1000, a competitor enters the shop and sees it, and then change the price to $995 at their shop. Suddenly you will notice that in a mattar of minutes, all your customers start to buy from the other shop. and you will lose xxxx number of customers before you know that they have under-cut you.
PC shops in SLS have already been hurt by such practises and as such, the prices for big ticket items like LCD Monitors, then to be $10xx or $5X5 or ASK, to discourage other shops from undercutting them, the customers will have to ask the shop and depending on who you ask, (boss or not boss) the amount quoted may differ slightly.